diff --git a/mozilla/layout/base/nsDisplayList.cpp b/mozilla/layout/base/nsDisplayList.cpp
index 4bdbe99a432..ff4bc6c6e44 100644
--- a/mozilla/layout/base/nsDisplayList.cpp
+++ b/mozilla/layout/base/nsDisplayList.cpp
@@ -346,9 +346,7 @@ nsIFrame* nsDisplayList::HitTest(nsDisplayListBuilder* aBuilder, nsPoint aPt) co
       nsIFrame* f = item->HitTest(aBuilder, aPt);
       // Handle the XUL 'mousethrough' feature.
       if (f) {
-        PRBool mouseThrough = PR_FALSE;
-        f->GetMouseThrough(mouseThrough);
-        if (!mouseThrough)
+        if (!f->GetMouseThrough())
           return f;
       }
     }
diff --git a/mozilla/layout/forms/nsTextControlFrame.cpp b/mozilla/layout/forms/nsTextControlFrame.cpp
index 4d4277fd74c..74182521be2 100644
--- a/mozilla/layout/forms/nsTextControlFrame.cpp
+++ b/mozilla/layout/forms/nsTextControlFrame.cpp
@@ -1821,28 +1821,25 @@ nsTextControlFrame::GetMaxSize(nsBoxLayoutState& aState)
   return nsBox::GetMaxSize(aState);
 }
 
-NS_IMETHODIMP
-nsTextControlFrame::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
+nscoord
+nsTextControlFrame::GetBoxAscent(nsBoxLayoutState& aState)
 {
   // First calculate the ascent of the text inside
-  nsresult rv = nsStackFrame::GetAscent(aState, aAscent);
-  NS_ENSURE_SUCCESS(rv, rv);
+  nscoord ascent = nsStackFrame::GetBoxAscent(aState);
     
   // Now adjust the ascent for our borders and padding
   nsMargin borderPadding;
   GetBorderAndPadding(borderPadding);
-  aAscent += borderPadding.top;
+  ascent += borderPadding.top;
   
-  return NS_OK;
+  return ascent;
 }
 
-NS_IMETHODIMP
-nsTextControlFrame::IsCollapsed(nsBoxLayoutState& aBoxLayoutState,
-                                PRBool& aCollapsed)
+PRBool
+nsTextControlFrame::IsCollapsed(nsBoxLayoutState& aBoxLayoutState)
 {
   // We're never collapsed in the box sense.
-  aCollapsed = PR_FALSE;
-  return NS_OK;
+  return PR_FALSE;
 }
 
 PRBool
diff --git a/mozilla/layout/forms/nsTextControlFrame.h b/mozilla/layout/forms/nsTextControlFrame.h
index 3e19c525430..c2adf0cb7e4 100644
--- a/mozilla/layout/forms/nsTextControlFrame.h
+++ b/mozilla/layout/forms/nsTextControlFrame.h
@@ -89,9 +89,8 @@ public:
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent);
-  NS_IMETHOD IsCollapsed(nsBoxLayoutState& aBoxLayoutState,
-                         PRBool& aCollapsed);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState);
+  virtual PRBool IsCollapsed(nsBoxLayoutState& aBoxLayoutState);
 
   DECL_DO_GLOBAL_REFLOW_COUNT_DSP(nsTextControlFrame, nsStackFrame)
 
diff --git a/mozilla/layout/generic/nsFrame.cpp b/mozilla/layout/generic/nsFrame.cpp
index 7e2249e9e3f..dc4ef994c28 100644
--- a/mozilla/layout/generic/nsFrame.cpp
+++ b/mozilla/layout/generic/nsFrame.cpp
@@ -146,9 +146,7 @@ struct nsBoxLayoutMetrics
   nscoord mAscent;
 
   nsSize mLastSize;
-  nsSize mOverflow;
 
-  PRPackedBool mIncludeOverflow;
   PRPackedBool mWasCollapsed;
 };
 
@@ -5772,20 +5770,6 @@ void nsFrame::FillCursorInformationFromStyle(const nsStyleUserInterface* ui,
   }
 }
 
-NS_IMETHODIMP
-nsFrame::GetOverflow(nsSize& aOverflow)
-{
-  aOverflow = BoxMetrics()->mOverflow;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsFrame::SetIncludeOverflow(PRBool aInclude)
-{
-  BoxMetrics()->mIncludeOverflow = aInclude;
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsFrame::RefreshSizeCache(nsBoxLayoutState& aState)
 {
@@ -5900,9 +5884,7 @@ nsFrame::GetPrefSize(nsBoxLayoutState& aState)
     return size;
   }
 
-  PRBool isCollapsed = PR_FALSE;
-  IsCollapsed(aState, isCollapsed);
-  if (isCollapsed)
+  if (IsCollapsed(aState))
     return size;
 
   // get our size in CSS.
@@ -5936,9 +5918,7 @@ nsFrame::GetMinSize(nsBoxLayoutState& aState)
     return size;
   }
 
-  PRBool isCollapsed = PR_FALSE;
-  IsCollapsed(aState, isCollapsed);
-  if (isCollapsed)
+  if (IsCollapsed(aState))
     return size;
 
   // get our size in CSS.
@@ -5968,9 +5948,7 @@ nsFrame::GetMaxSize(nsBoxLayoutState& aState)
     return size;
   }
 
-  PRBool isCollapsed = PR_FALSE;
-  IsCollapsed(aState, isCollapsed);
-  if (isCollapsed)
+  if (IsCollapsed(aState))
     return size;
 
   size = nsBox::GetMaxSize(aState);
@@ -5979,35 +5957,26 @@ nsFrame::GetMaxSize(nsBoxLayoutState& aState)
   return size;
 }
 
-NS_IMETHODIMP
-nsFrame::GetFlex(nsBoxLayoutState& aState, nscoord& aFlex)
+nscoord
+nsFrame::GetFlex(nsBoxLayoutState& aState)
 {
   nsBoxLayoutMetrics *metrics = BoxMetrics();
-  if (!DoesNeedRecalc(metrics->mFlex)) {
-     aFlex = metrics->mFlex;
-     return NS_OK;
-  }
+  if (!DoesNeedRecalc(metrics->mFlex))
+     return metrics->mFlex;
 
-  metrics->mFlex = 0;
-  nsBox::GetFlex(aState, metrics->mFlex);
+  metrics->mFlex = nsBox::GetFlex(aState);
 
-  aFlex = metrics->mFlex;
-
-  return NS_OK;
+  return metrics->mFlex;
 }
 
-NS_IMETHODIMP
-nsFrame::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
+nscoord
+nsFrame::GetBoxAscent(nsBoxLayoutState& aState)
 {
   nsBoxLayoutMetrics *metrics = BoxMetrics();
-  if (!DoesNeedRecalc(metrics->mAscent)) {
-    aAscent = metrics->mAscent;
-    return NS_OK;
-  }
+  if (!DoesNeedRecalc(metrics->mAscent))
+    return metrics->mAscent;
 
-  PRBool isCollapsed = PR_FALSE;
-  IsCollapsed(aState, isCollapsed);
-  if (isCollapsed) {
+  if (IsCollapsed(aState)) {
     metrics->mAscent = 0;
   } else {
     // Refresh our caches with new sizes.
@@ -6018,9 +5987,7 @@ nsFrame::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
     metrics->mAscent += m.top;
   }
 
-  aAscent = metrics->mAscent;
-
-  return NS_OK;
+  return metrics->mAscent;
 }
 
 nsresult
@@ -6038,9 +6005,7 @@ nsFrame::DoLayout(nsBoxLayoutState& aState)
     rv = BoxReflow(aState, presContext, desiredSize, rendContext,
                    ourRect.x, ourRect.y, ourRect.width, ourRect.height);
 
-    PRBool collapsed = PR_FALSE;
-    IsCollapsed(aState, collapsed);
-    if (collapsed) {
+    if (IsCollapsed(aState)) {
       SetSize(nsSize(0, 0));
     } else {
 
@@ -6242,48 +6207,40 @@ nsFrame::BoxReflow(nsBoxLayoutState&        aState,
 
     // see if the overflow option is set. If it is then if our child's bounds overflow then
     // we will set the child's rect to include the overflow size.
-       if (GetStateBits() & NS_FRAME_OUTSIDE_CHILDREN) {
-         // make sure we store the overflow size
+    if (GetStateBits() & NS_FRAME_OUTSIDE_CHILDREN) {
+      // make sure we store the overflow size
+      
+      // This kinda sucks. We should be able to handle the case
+      // where there's overflow above or to the left of the
+      // origin. But for now just chop that stuff off.
 
-         // This kinda sucks. We should be able to handle the case
-         // where there's overflow above or to the left of the
-         // origin. But for now just chop that stuff off.
-         metrics->mOverflow.width = aDesiredSize.mOverflowArea.XMost();
-         metrics->mOverflow.height = aDesiredSize.mOverflowArea.YMost();
+      //printf("OutsideChildren width=%d, height=%d\n", aDesiredSize.mOverflowArea.width, aDesiredSize.mOverflowArea.height);
+      aDesiredSize.width = aDesiredSize.mOverflowArea.XMost();
+      if (aDesiredSize.width <= aWidth)
+        aDesiredSize.height = aDesiredSize.mOverflowArea.YMost();
+      else {
+        if (aDesiredSize.width > aWidth)
+        {
+          nscoord computedWidth = aDesiredSize.width -
+            reflowState.mComputedBorderPadding.LeftRight();
+          computedWidth = PR_MAX(computedWidth, 0);
+          reflowState.SetComputedWidth(computedWidth);
+          reflowState.availableWidth = aDesiredSize.width;
+          DidReflow(aPresContext, &reflowState, NS_FRAME_REFLOW_FINISHED);
+          #ifdef DEBUG_REFLOW
+           nsAdaptorAddIndents();
+           nsAdaptorPrintReason(reflowState);
+           printf("\n");
+          #endif
+          AddStateBits(NS_FRAME_IS_DIRTY);
+          WillReflow(aPresContext);
+          Reflow(aPresContext, aDesiredSize, reflowState, status);
+          if (GetStateBits() & NS_FRAME_OUTSIDE_CHILDREN)
+            aDesiredSize.height = aDesiredSize.mOverflowArea.YMost();
 
-         // include the overflow size in our child's rect?
-         if (metrics->mIncludeOverflow) {
-             //printf("OutsideChildren width=%d, height=%d\n", aDesiredSize.mOverflowArea.width, aDesiredSize.mOverflowArea.height);
-             aDesiredSize.width = aDesiredSize.mOverflowArea.XMost();
-             if (aDesiredSize.width <= aWidth)
-               aDesiredSize.height = aDesiredSize.mOverflowArea.YMost();
-             else {
-              if (aDesiredSize.width > aWidth)
-              {
-                 nscoord computedWidth = aDesiredSize.width -
-                   reflowState.mComputedBorderPadding.LeftRight();
-                 computedWidth = PR_MAX(computedWidth, 0);
-                 reflowState.SetComputedWidth(computedWidth);
-                 reflowState.availableWidth = aDesiredSize.width;
-                 DidReflow(aPresContext, &reflowState, NS_FRAME_REFLOW_FINISHED);
-                 #ifdef DEBUG_REFLOW
-                  nsAdaptorAddIndents();
-                  nsAdaptorPrintReason(reflowState);
-                  printf("\n");
-                 #endif
-                 AddStateBits(NS_FRAME_IS_DIRTY);
-                 WillReflow(aPresContext);
-                 Reflow(aPresContext, aDesiredSize, reflowState, status);
-                 if (GetStateBits() & NS_FRAME_OUTSIDE_CHILDREN)
-                    aDesiredSize.height = aDesiredSize.mOverflowArea.YMost();
-
-              }
-             }
-         }
-       } else {
-         metrics->mOverflow.width  = aDesiredSize.width;
-         metrics->mOverflow.height = aDesiredSize.height;
-       }
+        }
+      }
+    }
 
     if (redrawAfterReflow) {
        nsRect r = GetRect();
@@ -6302,9 +6259,7 @@ nsFrame::BoxReflow(nsBoxLayoutState&        aState,
                                         aDesiredSize, aX, aY, layoutFlags | NS_FRAME_NO_MOVE_FRAME);
 
     // Save the ascent.  (bug 103925)
-    PRBool isCollapsed = PR_FALSE;
-    IsCollapsed(aState, isCollapsed);
-    if (isCollapsed) {
+    if (IsCollapsed(aState)) {
       metrics->mAscent = 0;
     } else {
       if (aDesiredSize.ascent == nsHTMLReflowMetrics::ASK_FOR_BASELINE) {
@@ -6381,9 +6336,7 @@ nsFrame::SetParent(const nsIFrame* aParent)
     DeleteProperty(nsGkAtoms::boxMetricsProperty);
 
   if (aParent && aParent->IsBoxFrame()) {
-    PRBool needsWidget = PR_FALSE;
-    aParent->ChildrenMustHaveWidgets(needsWidget);
-    if (needsWidget) {
+    if (aParent->ChildrenMustHaveWidgets()) {
         nsHTMLContainerFrame::CreateViewForFrame(this, nsnull, PR_TRUE);
         nsIView* view = GetView();
         if (!view->HasWidget())
@@ -6415,8 +6368,6 @@ nsFrame::InitBoxMetrics(PRBool aClear)
   nsFrame::MarkIntrinsicWidthsDirty();
   metrics->mBlockAscent = 0;
   metrics->mLastSize.SizeTo(0, 0);
-  metrics->mOverflow.SizeTo(0, 0);
-  metrics->mIncludeOverflow = PR_TRUE;
   metrics->mWasCollapsed = PR_FALSE;
 }
 
diff --git a/mozilla/layout/generic/nsFrame.h b/mozilla/layout/generic/nsFrame.h
index 7a7ab624181..286c135635c 100644
--- a/mozilla/layout/generic/nsFrame.h
+++ b/mozilla/layout/generic/nsFrame.h
@@ -363,10 +363,8 @@ public:
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState);
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent);
-  NS_IMETHOD SetIncludeOverflow(PRBool aInclude);
-  NS_IMETHOD GetOverflow(nsSize& aOverflow);
+  virtual nscoord GetFlex(nsBoxLayoutState& aBoxLayoutState);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState);
 
   //--------------------------------------------------
   // Additional methods
diff --git a/mozilla/layout/generic/nsGfxScrollFrame.cpp b/mozilla/layout/generic/nsGfxScrollFrame.cpp
index 73f0d615a01..b5cf3fcd0ac 100644
--- a/mozilla/layout/generic/nsGfxScrollFrame.cpp
+++ b/mozilla/layout/generic/nsGfxScrollFrame.cpp
@@ -1041,23 +1041,22 @@ nsXULScrollFrame::GetType() const
   return nsGkAtoms::scrollFrame; 
 }
 
-NS_IMETHODIMP
-nsXULScrollFrame::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
+nscoord
+nsXULScrollFrame::GetBoxAscent(nsBoxLayoutState& aState)
 {
-  aAscent = 0;
   if (!mInner.mScrolledFrame)
-    return NS_OK;
+    return 0;
 
-  nsresult rv = mInner.mScrolledFrame->GetAscent(aState, aAscent);
+  nscoord ascent = mInner.mScrolledFrame->GetBoxAscent(aState);
   nsMargin m(0,0,0,0);
   GetBorderAndPadding(m);
-  aAscent += m.top;
+  ascent += m.top;
   GetMargin(m);
-  aAscent += m.top;
+  ascent += m.top;
   GetInset(m);
-  aAscent += m.top;
+  ascent += m.top;
 
-  return rv;
+  return ascent;
 }
 
 nsSize
diff --git a/mozilla/layout/generic/nsGfxScrollFrame.h b/mozilla/layout/generic/nsGfxScrollFrame.h
index 47c8dfa3e84..565e5a6e34d 100644
--- a/mozilla/layout/generic/nsGfxScrollFrame.h
+++ b/mozilla/layout/generic/nsGfxScrollFrame.h
@@ -478,7 +478,7 @@ public:
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState);
 
   NS_IMETHOD DoLayout(nsBoxLayoutState& aBoxLayoutState);
   NS_IMETHOD GetPadding(nsMargin& aPadding);
diff --git a/mozilla/layout/generic/nsIFrame.h b/mozilla/layout/generic/nsIFrame.h
index 46d0cab0fa3..018d92200cf 100644
--- a/mozilla/layout/generic/nsIFrame.h
+++ b/mozilla/layout/generic/nsIFrame.h
@@ -100,10 +100,10 @@ struct nsMargin;
 typedef class nsIFrame nsIBox;
 
 // IID for the nsIFrame interface 
-// f02b2868-ac80-4e38-978c-02df6477d294
+// 4ea7876f-1550-40d4-a764-739a0e4289a1
 #define NS_IFRAME_IID \
-{ 0xf02b2868, 0xac80, 0x4e38, \
-  { 0x97, 0x8c, 0x02, 0xdf, 0x64, 0x77, 0xd2, 0x94 } }
+{ 0x4ea7876f, 0x1550, 0x40d4, \
+  { 0xa7, 0x64, 0x73, 0x9a, 0x0e, 0x42, 0x89, 0xa1 } }
 
 /**
  * Indication of how the frame can be split. This is used when doing runaround
@@ -1845,18 +1845,18 @@ NS_PTR_TO_INT32(frame->GetProperty(nsGkAtoms::embeddingLevel))
    */    
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState) = 0;
 
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex)=0;
-  NS_HIDDEN_(nsresult)
-    GetOrdinal(nsBoxLayoutState& aBoxLayoutState, PRUint32& aOrdinal);
-
   /**
    * This returns the minimum size for the scroll area if this frame is
    * being scrolled. Usually it's (0,0).
    */
   virtual nsSize GetMinSizeForScrollArea(nsBoxLayoutState& aBoxLayoutState) = 0;
 
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent)=0;
-  NS_IMETHOD IsCollapsed(nsBoxLayoutState& aBoxLayoutState, PRBool& aCollapsed)=0;
+  // Implemented in nsBox, used in nsBoxFrame
+  PRUint32 GetOrdinal(nsBoxLayoutState& aBoxLayoutState);
+
+  virtual nscoord GetFlex(nsBoxLayoutState& aBoxLayoutState) = 0;
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState) = 0;
+  virtual PRBool IsCollapsed(nsBoxLayoutState& aBoxLayoutState) = 0;
   // This does not alter the overflow area. If the caller is changing
   // the box size, the caller is responsible for updating the overflow
   // area. It's enough to just call Layout or SyncLayout on the
@@ -1891,24 +1891,16 @@ NS_PTR_TO_INT32(frame->GetProperty(nsGkAtoms::embeddingLevel))
   NS_IMETHOD GetMargin(nsMargin& aMargin)=0;
   NS_IMETHOD SetLayoutManager(nsIBoxLayout* aLayout)=0;
   NS_IMETHOD GetLayoutManager(nsIBoxLayout** aLayout)=0;
-  NS_HIDDEN_(nsresult) GetContentRect(nsRect& aContentRect);
   NS_HIDDEN_(nsresult) GetClientRect(nsRect& aContentRect);
   NS_IMETHOD GetVAlign(Valignment& aAlign) = 0;
   NS_IMETHOD GetHAlign(Halignment& aAlign) = 0;
 
   PRBool IsHorizontal() const { return (mState & NS_STATE_IS_HORIZONTAL) != 0; }
-  nsresult GetOrientation(PRBool& aIsHorizontal)  /// XXX to be removed
-  { aIsHorizontal = IsHorizontal(); return NS_OK; }
-
   PRBool IsNormalDirection() const { return (mState & NS_STATE_IS_DIRECTION_NORMAL) != 0; }
-  nsresult GetDirection(PRBool& aIsNormal)  /// XXX to be removed
-  { aIsNormal = IsNormalDirection(); return NS_OK; }
 
   NS_HIDDEN_(nsresult) Redraw(nsBoxLayoutState& aState, const nsRect* aRect = nsnull, PRBool aImmediate = PR_FALSE);
   NS_IMETHOD RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild)=0;
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough)=0;
-  NS_IMETHOD SetIncludeOverflow(PRBool aInclude) = 0;
-  NS_IMETHOD GetOverflow(nsSize& aOverflow) = 0;
+  virtual PRBool GetMouseThrough() const = 0;
 
 #ifdef DEBUG_LAYOUT
   NS_IMETHOD SetDebug(nsBoxLayoutState& aState, PRBool aDebug)=0;
@@ -1916,8 +1908,9 @@ NS_PTR_TO_INT32(frame->GetProperty(nsGkAtoms::embeddingLevel))
 
   NS_IMETHOD DumpBox(FILE* out)=0;
 #endif
-  NS_IMETHOD ChildrenMustHaveWidgets(PRBool& aMust) const=0;
-  NS_IMETHOD GetIndexOf(nsIBox* aChild, PRInt32* aIndex)=0;
+
+  // Only nsDeckFrame requires that all its children have widgets
+  virtual PRBool ChildrenMustHaveWidgets() const { return PR_FALSE; }
 
   /**
    * @return PR_TRUE if this text frame ends with a newline character.  It
diff --git a/mozilla/layout/xul/base/src/grid/nsGrid.cpp b/mozilla/layout/xul/base/src/grid/nsGrid.cpp
index 0a4369cb50f..1a434a69035 100644
--- a/mozilla/layout/xul/base/src/grid/nsGrid.cpp
+++ b/mozilla/layout/xul/base/src/grid/nsGrid.cpp
@@ -749,12 +749,8 @@ nsGrid::GetRowOffsets(nsBoxLayoutState& aState, PRInt32 aIndex, nscoord& aTop, n
   // borders padding and insets into account
   if (box && !row->mIsBogus)
   {
-     PRBool isCollapsed = PR_FALSE;
-     box->IsCollapsed(aState, isCollapsed);
-
-     if (!isCollapsed) 
-     {
-
+    if (!box->IsCollapsed(aState))
+    {
        box->GetInset(inset);
 
        // get real border and padding. GetBorderAndPadding
@@ -823,9 +819,7 @@ nsGrid::GetRowOffsets(nsBoxLayoutState& aState, PRInt32 aIndex, nscoord& aTop, n
       if (box) 
       {
         // ignore collapsed children
-        box->IsCollapsed(aState, isCollapsed);
-
-        if (!isCollapsed)
+        if (!box->IsCollapsed(aState))
         {
            // include the margin of the columns. To the row
            // at this point border/padding and margins all added
@@ -1222,8 +1216,7 @@ nsGrid::GetRowFlex(nsBoxLayoutState& aState, PRInt32 aIndex, PRBool aIsHorizonta
       // not flexible.
       if (parentsParent) {
         if (!IsGrid(parentsParent)) {
-          nscoord flex = 0;
-          parent->GetFlex(aState, flex);
+          nscoord flex = parent->GetFlex(aState);
           nsIBox::AddCSSFlex(aState, parent, flex);
           if (flex == 0) {
             row->mFlex = 0;
@@ -1237,9 +1230,8 @@ nsGrid::GetRowFlex(nsBoxLayoutState& aState, PRInt32 aIndex, PRBool aIsHorizonta
     }
     
     // get the row flex.
-    box->GetFlex(aState, row->mFlex);
+    row->mFlex = box->GetFlex(aState);
     nsIBox::AddCSSFlex(aState, box, row->mFlex);
-
   }
 
   return row->mFlex;
diff --git a/mozilla/layout/xul/base/src/grid/nsGridCell.cpp b/mozilla/layout/xul/base/src/grid/nsGridCell.cpp
index d5e2bd41e72..9cca284b421 100644
--- a/mozilla/layout/xul/base/src/grid/nsGridCell.cpp
+++ b/mozilla/layout/xul/base/src/grid/nsGridCell.cpp
@@ -152,15 +152,8 @@ nsGridCell::GetMaxSize(nsBoxLayoutState& aState)
 PRBool
 nsGridCell::IsCollapsed(nsBoxLayoutState& aState)
 {
-  PRBool c1 = PR_FALSE, c2 = PR_FALSE;
-
-  if (mBoxInColumn) 
-    mBoxInColumn->IsCollapsed(aState, c1);
-
-  if (mBoxInRow) 
-    mBoxInRow->IsCollapsed(aState, c2);
-
-  return (c1 || c2);
+  return ((mBoxInColumn && mBoxInColumn->IsCollapsed(aState)) ||
+          (mBoxInRow && mBoxInRow->IsCollapsed(aState)));
 }
 
 
diff --git a/mozilla/layout/xul/base/src/grid/nsGridRow.cpp b/mozilla/layout/xul/base/src/grid/nsGridRow.cpp
index 7f49a28e427..202d331fe85 100644
--- a/mozilla/layout/xul/base/src/grid/nsGridRow.cpp
+++ b/mozilla/layout/xul/base/src/grid/nsGridRow.cpp
@@ -100,11 +100,6 @@ nsGridRow::MarkDirty(nsBoxLayoutState& aState)
 PRBool 
 nsGridRow::IsCollapsed(nsBoxLayoutState& aState)
 {
-  PRBool isCollapsed = PR_FALSE;
-
-  if (mBox)
-    mBox->IsCollapsed(aState,isCollapsed);
-
-  return isCollapsed;
+  return mBox && mBox->IsCollapsed(aState);
 }
 
diff --git a/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.cpp b/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.cpp
index 0743f872cd6..408adf24992 100644
--- a/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.cpp
+++ b/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.cpp
@@ -64,23 +64,18 @@ NS_NewGridRowGroupFrame (nsIPresShell* aPresShell,
  * This is redefined because row groups have a funny property. If they are flexible
  * then their flex must be equal to the sum of their children's flexes.
  */
-NS_IMETHODIMP
-nsGridRowGroupFrame::GetFlex(nsBoxLayoutState& aState, nscoord& aFlex)
+nscoord
+nsGridRowGroupFrame::GetFlex(nsBoxLayoutState& aState)
 {
   // if we are flexible out flexibility is determined by our columns.
   // so first get the our flex. If not 0 then our flex is the sum of
   // our columns flexes.
 
-  if (!DoesNeedRecalc(mFlex)) {
-     aFlex = mFlex;
-     return NS_OK;
-  }
+  if (!DoesNeedRecalc(mFlex))
+     return mFlex;
 
-  nsBoxFrame::GetFlex(aState, aFlex);
-
-
-  if (aFlex == 0)
-    return NS_OK;
+  if (nsBoxFrame::GetFlex(aState) == 0)
+    return 0;
 
   // ok we are flexible add up our children
   nscoord totalFlex = 0;
@@ -88,16 +83,13 @@ nsGridRowGroupFrame::GetFlex(nsBoxLayoutState& aState, nscoord& aFlex)
   GetChildBox(&child);
   while (child)
   {
-    PRInt32 flex = 0;
-    child->GetFlex(aState, flex);
-    totalFlex += flex;;
+    totalFlex += child->GetFlex(aState);
     child->GetNextBox(&child);
   }
 
-  aFlex = totalFlex;
-  mFlex = aFlex;
+  mFlex = totalFlex;
 
-  return NS_OK;
+  return totalFlex;
 }
 
 
diff --git a/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.h b/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.h
index d1b2c1d1659..ec432f16e05 100644
--- a/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.h
+++ b/mozilla/layout/xul/base/src/grid/nsGridRowGroupFrame.h
@@ -75,7 +75,7 @@ public:
                       nsIBoxLayout* aLayoutManager):
     nsBoxFrame(aPresShell, aContext, aIsRoot, aLayoutManager) {}
 
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex);
+  virtual nscoord GetFlex(nsBoxLayoutState& aBoxLayoutState);
 
 }; // class nsGridRowGroupFrame
 
diff --git a/mozilla/layout/xul/base/src/grid/nsGridRowLeafLayout.cpp b/mozilla/layout/xul/base/src/grid/nsGridRowLeafLayout.cpp
index df8eaa766b1..86cd423de62 100644
--- a/mozilla/layout/xul/base/src/grid/nsGridRowLeafLayout.cpp
+++ b/mozilla/layout/xul/base/src/grid/nsGridRowLeafLayout.cpp
@@ -176,7 +176,7 @@ nsGridRowLeafLayout::PopulateBoxSizes(nsIBox* aBox, nsBoxLayoutState& aState, ns
      nscoord bottomMargin = column->mBottomMargin;
 
      if (box) 
-       box->IsCollapsed(aState, collapsed);
+       collapsed = box->IsCollapsed(aState);
 
      pref = pref - (left + right);
      if (pref < 0)
@@ -264,9 +264,6 @@ nsGridRowLeafLayout::ComputeChildSizes(nsIBox* aBox,
   if (aBox) {
 
      // go up the parent chain looking for scrollframes
-     PRBool isHorizontal = PR_FALSE;
-     aBox->GetOrientation(isHorizontal);
-
      nsIBox* scrollbox = nsnull;
      aBox->GetParentBox(&aBox);
      scrollbox = nsGrid::GetScrollBox(aBox);
@@ -283,7 +280,7 @@ nsGridRowLeafLayout::ComputeChildSizes(nsIBox* aBox,
           ourRect.Deflate(padding);
 
           nscoord diff;
-          if (isHorizontal) {
+          if (aBox->IsHorizontal()) {
             diff = scrollbarSizes.left + scrollbarSizes.right;
           } else {
             diff = scrollbarSizes.top + scrollbarSizes.bottom;
diff --git a/mozilla/layout/xul/base/src/nsBox.cpp b/mozilla/layout/xul/base/src/nsBox.cpp
index 2841a0e0c31..ad1aa786bd8 100644
--- a/mozilla/layout/xul/base/src/nsBox.cpp
+++ b/mozilla/layout/xul/base/src/nsBox.cpp
@@ -151,16 +151,6 @@ nsBox::PropagateDebug(nsBoxLayoutState& aState)
 }
 #endif
 
-/**
- * Hack for deck who requires that all its children has widgets
- */
-NS_IMETHODIMP 
-nsBox::ChildrenMustHaveWidgets(PRBool& aMust) const
-{
-  aMust = PR_FALSE;
-  return NS_OK;
-}
-
 #ifdef DEBUG_LAYOUT
 void
 nsBox::GetBoxName(nsAutoString& aName)
@@ -280,7 +270,8 @@ nsBox::GetHAlign(Halignment& aAlign)
 nsresult
 nsIFrame::GetClientRect(nsRect& aClientRect)
 {
-  GetContentRect(aClientRect);
+  aClientRect = mRect;
+  aClientRect.MoveTo(0,0);
 
   nsMargin borderPadding;
   GetBorderAndPadding(borderPadding);
@@ -302,16 +293,6 @@ nsIFrame::GetClientRect(nsRect& aClientRect)
   return NS_OK;
 }
 
-nsresult
-nsIFrame::GetContentRect(nsRect& aContentRect)
-{
-  aContentRect = mRect;
-  aContentRect.x = 0;
-  aContentRect.y = 0;
-  NS_BOX_ASSERTION(this, aContentRect.width >=0 && aContentRect.height >= 0, "Content Size < 0");
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsBox::SetBounds(nsBoxLayoutState& aState, const nsRect& aRect, PRBool aRemoveOverflowArea)
 {
@@ -523,9 +504,7 @@ nsBox::GetPrefSize(nsBoxLayoutState& aState)
   nsSize pref(0,0);
   DISPLAY_PREF_SIZE(this, pref);
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aState))
     return pref;
 
   AddBorderAndPadding(pref);
@@ -545,9 +524,7 @@ nsBox::GetMinSize(nsBoxLayoutState& aState)
   nsSize min(0,0);
   DISPLAY_MIN_SIZE(this, min);
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aState))
     return min;
 
   AddBorderAndPadding(min);
@@ -568,9 +545,7 @@ nsBox::GetMaxSize(nsBoxLayoutState& aState)
   nsSize max(NS_INTRINSICSIZE, NS_INTRINSICSIZE);
   DISPLAY_MAX_SIZE(this, max);
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aState))
     return max;
 
   AddBorderAndPadding(max);
@@ -579,46 +554,42 @@ nsBox::GetMaxSize(nsBoxLayoutState& aState)
   return max;
 }
 
-NS_IMETHODIMP
-nsBox::GetFlex(nsBoxLayoutState& aState, nscoord& aFlex)
+nscoord
+nsBox::GetFlex(nsBoxLayoutState& aState)
 {
-  aFlex = 0;
+  nscoord flex = 0;
 
-  GetDefaultFlex(aFlex);
-  nsIBox::AddCSSFlex(aState, this, aFlex);
+  GetDefaultFlex(flex);
+  nsIBox::AddCSSFlex(aState, this, flex);
 
-  return NS_OK;
+  return flex;
 }
 
-nsresult
-nsIFrame::GetOrdinal(nsBoxLayoutState& aState, PRUint32& aOrdinal)
+PRUint32
+nsIFrame::GetOrdinal(nsBoxLayoutState& aState)
 {
-  aOrdinal = DEFAULT_ORDINAL_GROUP;
-  nsIBox::AddCSSOrdinal(aState, this, aOrdinal);
+  PRUint32 ordinal = DEFAULT_ORDINAL_GROUP;
+  nsIBox::AddCSSOrdinal(aState, this, ordinal);
 
-  return NS_OK;
+  return ordinal;
 }
 
-NS_IMETHODIMP
-nsBox::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
+nscoord
+nsBox::GetBoxAscent(nsBoxLayoutState& aState)
+{
+  if (IsCollapsed(aState))
+    return 0;
+
+  return GetPrefSize(aState).height;
+}
+
+PRBool
+nsBox::IsCollapsed(nsBoxLayoutState& aState)
 {
-  aAscent = 0;
   PRBool collapsed = PR_FALSE;
-  IsCollapsed(aState, collapsed);
-  if (collapsed)
-    return NS_OK;
+  nsIBox::AddCSSCollapsed(aState, this, collapsed);
 
-  aAscent = GetPrefSize(aState).height;
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsBox::IsCollapsed(nsBoxLayoutState& aState, PRBool& aCollapsed)
-{
-  aCollapsed = PR_FALSE;
-  nsIBox::AddCSSCollapsed(aState, this, aCollapsed);
-
-  return NS_OK;
+  return collapsed;
 }
 
 nsresult
@@ -1168,14 +1139,13 @@ nsBox::GetInset(nsMargin& margin)
 
 #endif
 
-NS_IMETHODIMP
-nsBox::GetMouseThrough(PRBool& aMouseThrough)
+PRBool
+nsBox::GetMouseThrough() const
 {
   if (mParent && mParent->IsBoxFrame())
-    return mParent->GetMouseThrough(aMouseThrough);
+    return mParent->GetMouseThrough();
 
-  aMouseThrough = PR_FALSE;
-  return NS_OK;
+  return PR_FALSE;
 }
 
 PRBool
@@ -1184,11 +1154,3 @@ nsBox::GetDefaultFlex(PRInt32& aFlex)
   aFlex = 0; 
   return PR_TRUE; 
 }
-
-NS_IMETHODIMP
-nsBox::GetIndexOf(nsIBox* aChild, PRInt32* aIndex)
-{
-  // return -1. We have no children
-  *aIndex = -1;
-  return NS_OK;
-}
diff --git a/mozilla/layout/xul/base/src/nsBox.h b/mozilla/layout/xul/base/src/nsBox.h
index 7d184934bfb..d8a4be5e381 100644
--- a/mozilla/layout/xul/base/src/nsBox.h
+++ b/mozilla/layout/xul/base/src/nsBox.h
@@ -60,12 +60,12 @@ public:
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState);
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent);
+  virtual nscoord GetFlex(nsBoxLayoutState& aBoxLayoutState);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState);
 
   virtual nsSize GetMinSizeForScrollArea(nsBoxLayoutState& aBoxLayoutState);
 
-  NS_IMETHOD IsCollapsed(nsBoxLayoutState& aBoxLayoutState, PRBool& aCollapsed);
+  virtual PRBool IsCollapsed(nsBoxLayoutState& aBoxLayoutState);
 
   NS_IMETHOD SetBounds(nsBoxLayoutState& aBoxLayoutState, const nsRect& aRect,
                        PRBool aRemoveOverflowArea = PR_FALSE);
@@ -83,7 +83,7 @@ public:
 
   NS_IMETHOD RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild);
 
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough);
+  virtual PRBool GetMouseThrough() const;
 
 #ifdef DEBUG_LAYOUT
   NS_IMETHOD GetInset(nsMargin& aInset);
@@ -94,8 +94,6 @@ public:
   NS_IMETHOD DumpBox(FILE* out);
   NS_HIDDEN_(void) PropagateDebug(nsBoxLayoutState& aState);
 #endif
-  NS_IMETHOD ChildrenMustHaveWidgets(PRBool& aMust) const;
-  NS_IMETHOD GetIndexOf(nsIBox* aChild, PRInt32* aIndex);
 
   nsBox();
   virtual ~nsBox();
diff --git a/mozilla/layout/xul/base/src/nsBoxFrame.cpp b/mozilla/layout/xul/base/src/nsBoxFrame.cpp
index f978947b8be..b90da765916 100644
--- a/mozilla/layout/xul/base/src/nsBoxFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsBoxFrame.cpp
@@ -220,9 +220,7 @@ nsBoxFrame::Init(nsIContent*      aContent,
 
   // see if we need a widget
   if (aParent && aParent->IsBoxFrame()) {
-    PRBool needsWidget = PR_FALSE;
-    aParent->ChildrenMustHaveWidgets(needsWidget);
-    if (needsWidget) {
+    if (aParent->ChildrenMustHaveWidgets()) {
         nsHTMLContainerFrame::CreateViewForFrame(this, nsnull, PR_TRUE);
 
         nsIView* view = GetView();
@@ -263,29 +261,21 @@ void nsBoxFrame::UpdateMouseThrough()
   }
 }
 
-NS_IMETHODIMP
-nsBoxFrame::GetMouseThrough(PRBool& aMouseThrough)
+PRBool
+nsBoxFrame::GetMouseThrough() const
 {
   switch(mMouseThrough)
   {
     case always:
-      aMouseThrough = PR_TRUE;
-      return NS_OK;
+      return PR_TRUE;
     case never:
-      aMouseThrough = PR_FALSE;      
-      return NS_OK;
+      return PR_FALSE;
     case unset:
-    {
       if (mParent && mParent->IsBoxFrame())
-        return mParent->GetMouseThrough(aMouseThrough);
-      else {
-        aMouseThrough = PR_FALSE;      
-        return NS_OK;
-      }
-    }
+        return mParent->GetMouseThrough();
   }
 
-  return NS_ERROR_FAILURE;
+  return PR_FALSE;
 }
 
 void
@@ -793,7 +783,7 @@ nsBoxFrame::Reflow(nsPresContext*          aPresContext,
   // getting the ascent could be a lot of work. Don't get it if
   // we are the root. The viewport doesn't care about it.
   if (!(mState & NS_STATE_IS_ROOT)) {
-    GetAscent(state, ascent);
+    ascent = GetBoxAscent(state);
   }
 
   aDesiredSize.width  = mRect.width;
@@ -840,9 +830,7 @@ nsBoxFrame::GetPrefSize(nsBoxLayoutState& aBoxLayoutState)
   PropagateDebug(aBoxLayoutState);
 #endif
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aBoxLayoutState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aBoxLayoutState))
     return size;
 
   // if the size was not completely redefined in CSS then ask our children
@@ -863,34 +851,25 @@ nsBoxFrame::GetPrefSize(nsBoxLayoutState& aBoxLayoutState)
   return size;
 }
 
-NS_IMETHODIMP
-nsBoxFrame::GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent)
+nscoord
+nsBoxFrame::GetBoxAscent(nsBoxLayoutState& aBoxLayoutState)
 {
-  if (!DoesNeedRecalc(mAscent)) {
-     aAscent = mAscent;
-     return NS_OK;
-  }
+  if (!DoesNeedRecalc(mAscent))
+     return mAscent;
 
 #ifdef DEBUG_LAYOUT
   PropagateDebug(aBoxLayoutState);
 #endif
 
-  nsresult rv = NS_OK;
-  aAscent = 0;
-
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aBoxLayoutState, collapsed);
-  if (collapsed)
-    return NS_OK;
+  if (IsCollapsed(aBoxLayoutState))
+    return 0;
 
   if (mLayoutManager)
-    rv = mLayoutManager->GetAscent(this, aBoxLayoutState, aAscent);
+    mLayoutManager->GetAscent(this, aBoxLayoutState, mAscent);
   else
-    rv = nsBox::GetAscent(aBoxLayoutState, aAscent);
+    mAscent = nsBox::GetBoxAscent(aBoxLayoutState);
 
-  mAscent = aAscent;
- 
-  return rv;
+  return mAscent;
 }
 
 nsSize
@@ -907,9 +886,7 @@ nsBoxFrame::GetMinSize(nsBoxLayoutState& aBoxLayoutState)
   PropagateDebug(aBoxLayoutState);
 #endif
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aBoxLayoutState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aBoxLayoutState))
     return size;
 
   // if the size was not completely redefined in CSS then ask our children
@@ -942,9 +919,7 @@ nsBoxFrame::GetMaxSize(nsBoxLayoutState& aBoxLayoutState)
   PropagateDebug(aBoxLayoutState);
 #endif
 
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aBoxLayoutState, collapsed);
-  if (collapsed)
+  if (IsCollapsed(aBoxLayoutState))
     return size;
 
   // if the size was not completely redefined in CSS then ask our children
@@ -963,21 +938,15 @@ nsBoxFrame::GetMaxSize(nsBoxLayoutState& aBoxLayoutState)
   return size;
 }
 
-NS_IMETHODIMP
-nsBoxFrame::GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex)
+nscoord
+nsBoxFrame::GetFlex(nsBoxLayoutState& aBoxLayoutState)
 {
-  if (!DoesNeedRecalc(mFlex)) {
-     aFlex = mFlex;
-     return NS_OK;
-  }
+  if (!DoesNeedRecalc(mFlex))
+     return mFlex;
 
-  nsresult rv = NS_OK;
+  mFlex = nsBox::GetFlex(aBoxLayoutState);
 
-  mFlex = 0;
-  rv = nsBox::GetFlex(aBoxLayoutState, mFlex);
-  aFlex = mFlex;
-
-  return rv;
+  return mFlex;
 }
 
 /**
@@ -1394,8 +1363,6 @@ nsBoxFrame::PaintXULDebugBackground(nsIRenderingContext& aRenderingContext,
                                     nsPoint aPt)
 {
   nsMargin border;
-  nsRect inner;
-
   GetBorder(border);
 
   nsMargin debugBorder;
@@ -1413,8 +1380,8 @@ nsBoxFrame::PaintXULDebugBackground(nsIRenderingContext& aRenderingContext,
   GetDebugPadding(debugPadding);
   PixelMarginToTwips(GetPresContext(), debugPadding);
 
-  GetContentRect(inner);
-  inner += aPt;
+  nsRect inner(mRect);
+  inner.MoveTo(aPt);
   inner.Deflate(debugMargin);
   inner.Deflate(border);
   //nsRect borderRect(inner);
@@ -1471,14 +1438,12 @@ nsBoxFrame::PaintXULDebugOverlay(nsIRenderingContext& aRenderingContext,
   GetDebugMargin(debugMargin);
   PixelMarginToTwips(GetPresContext(), debugMargin);
 
-  nsRect inner;
-  GetContentRect(inner);
-  inner += aPt;
+  nsRect inner(mRect);
+  inner.MoveTo(aPt);
   inner.Deflate(debugMargin);
   inner.Deflate(border);
 
   nscoord onePixel = GetPresContext()->IntScaledPixelsToTwips(1);
-  GetContentRect(r);
 
   GetChildBox(&kid);
   while (nsnull != kid) {
@@ -1505,14 +1470,9 @@ nsBoxFrame::PaintXULDebugOverlay(nsIRenderingContext& aRenderingContext,
     }
 
     nsBoxLayoutState state(GetPresContext());
-    nscoord flex = 0;
-    kid->GetFlex(state, flex);
+    nscoord flex = kid->GetFlex(state);
 
-    
-    PRBool isCollapsed = PR_FALSE;
-    kid->IsCollapsed(state, isCollapsed);
-
-    if (!isCollapsed) {
+    if (!kid->IsCollapsed(state)) {
       aRenderingContext.SetColor(NS_RGB(255,255,255));
 
       if (isHorizontal) 
@@ -1801,8 +1761,8 @@ nsBoxFrame::DisplayDebugInfoFor(nsIBox*  aBox,
     nscoord y = aPoint.y;
 
     // get the area inside our border but not our debug margins.
-    nsRect insideBorder;
-    aBox->GetContentRect(insideBorder);
+    nsRect insideBorder(aBox->mRect);
+    insideBorder.MoveTo(0,0):
     nsMargin border(0,0,0,0);
     aBox->GetBorderAndPadding(border);
     insideBorder.Deflate(border);
@@ -1862,10 +1822,6 @@ nsBoxFrame::DisplayDebugInfoFor(nsIBox*  aBox,
                     nsSize maxSizeCSS (NS_INTRINSICSIZE, NS_INTRINSICSIZE);
                     nscoord flexCSS = NS_INTRINSICSIZE;
 
-                    nscoord flexSize = 0;
-                    nscoord ascentSize = 0;
-
-
                     nsIBox::AddCSSPrefSize(state, child, prefSizeCSS);
                     nsIBox::AddCSSMinSize (state, child, minSizeCSS);
                     nsIBox::AddCSSMaxSize (state, child, maxSizeCSS);
@@ -1874,8 +1830,8 @@ nsBoxFrame::DisplayDebugInfoFor(nsIBox*  aBox,
                     nsSize prefSize = child->GetPrefSize(state);
                     nsSize minSize = child->GetMinSize(state);
                     nsSize maxSize = child->GetMaxSize(state);
-                    child->GetFlex(state, flexSize);
-                    child->GetAscent(state, ascentSize);
+                    nscoord flexSize = child->GetFlex(state);
+                    nscoord ascentSize = child->GetBoxAscent(state);
 
                     char min[100];
                     char pref[100];
@@ -2159,8 +2115,7 @@ nsBoxFrame::CheckBoxOrder(nsBoxLayoutState& aState)
   while (child) {
     ++childCount;
 
-    PRUint32 ordinal;
-    child->GetOrdinal(aState, ordinal);
+    PRUint32 ordinal = child->GetOrdinal(aState);
     if (ordinal != DEFAULT_ORDINAL_GROUP)
       orderBoxes = PR_TRUE;
 
@@ -2185,9 +2140,9 @@ nsBoxFrame::CheckBoxOrder(nsBoxLayoutState& aState)
   PRUint32 minOrd, jOrd;
   for(i = 0; i < childCount; i++) {
     min = i;
-    boxes[min]->GetOrdinal(aState, minOrd);
+    minOrd = boxes[min]->GetOrdinal(aState);
     for(j = i + 1; j < childCount; j++) {
-      boxes[j]->GetOrdinal(aState, jOrd);
+      jOrd = boxes[j]->GetOrdinal(aState);
       if (jOrd < minOrd) {
         min = j;
         minOrd = jOrd;
@@ -2241,8 +2196,7 @@ nsBoxFrame::LayoutChildAt(nsBoxLayoutState& aState, nsIBox* aBox, const nsRect&
 NS_IMETHODIMP
 nsBoxFrame::RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild)
 {
-  PRUint32 ord;
-  aChild->GetOrdinal(aState, ord);
+  PRUint32 ord = aChild->GetOrdinal(aState);
   
   nsIFrame *child = mFrames.FirstChild();
   nsIFrame *curPrevSib = nsnull, *newPrevSib = nsnull;
@@ -2254,8 +2208,7 @@ nsBoxFrame::RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild)
     else if (!foundPrevSib)
       curPrevSib = child;
 
-    PRUint32 ordCmp;
-    child->GetOrdinal(aState, ordCmp);
+    PRUint32 ordCmp = child->GetOrdinal(aState);
     if (ord < ordCmp)
       foundNewPrevSib = PR_TRUE;
     else if (!foundNewPrevSib && child != aChild)
@@ -2293,27 +2246,6 @@ nsBoxFrame::RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild)
   return NS_OK;
 }
 
-NS_IMETHODIMP
-nsBoxFrame::GetIndexOf(nsIBox* aBox, PRInt32* aIndex)
-{
-    nsIBox* child = mFrames.FirstChild();
-    PRInt32 count = 0;
-    while (child) 
-    {       
-      if (aBox == child) {
-          *aIndex = count;
-          return NS_OK;
-      }
-
-      child->GetNextBox(&child);
-      count++;
-    }
-
-    *aIndex = -1;
-
-    return NS_OK;
-}
-
 PRBool
 nsBoxFrame::GetWasCollapsed(nsBoxLayoutState& aState)
 {
diff --git a/mozilla/layout/xul/base/src/nsBoxFrame.h b/mozilla/layout/xul/base/src/nsBoxFrame.h
index 6a49b032b1b..eb8b8e28a08 100644
--- a/mozilla/layout/xul/base/src/nsBoxFrame.h
+++ b/mozilla/layout/xul/base/src/nsBoxFrame.h
@@ -98,13 +98,12 @@ public:
   NS_IMETHOD SetLayoutManager(nsIBoxLayout* aLayout);
   NS_IMETHOD GetLayoutManager(nsIBoxLayout** aLayout);
   NS_IMETHOD RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild);
-  NS_IMETHOD GetIndexOf(nsIBox* aChild, PRInt32* aIndex);
 
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState);
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aBoxLayoutState, nscoord& aFlex);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aBoxLayoutState, nscoord& aAscent);
+  virtual nscoord GetFlex(nsBoxLayoutState& aBoxLayoutState);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState);
 #ifdef DEBUG_LAYOUT
   NS_IMETHOD SetDebug(nsBoxLayoutState& aBoxLayoutState, PRBool aDebug);
   NS_IMETHOD GetDebug(PRBool& aDebug);
@@ -115,7 +114,7 @@ public:
   NS_IMETHOD GetHAlign(Halignment& aAlign);
   NS_IMETHOD DoLayout(nsBoxLayoutState& aBoxLayoutState);
 
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough);
+  virtual PRBool GetMouseThrough() const;
   virtual PRBool ComputesOwnOverflowArea() { return PR_FALSE; }
 
   // ----- child and sibling operations ---
diff --git a/mozilla/layout/xul/base/src/nsBoxLayout.cpp b/mozilla/layout/xul/base/src/nsBoxLayout.cpp
index f9b2cbbeae2..1eed2652e22 100644
--- a/mozilla/layout/xul/base/src/nsBoxLayout.cpp
+++ b/mozilla/layout/xul/base/src/nsBoxLayout.cpp
@@ -99,14 +99,16 @@ nsBoxLayout::AddInset(nsIBox* aBox, nsSize& aSize)
 NS_IMETHODIMP
 nsBoxLayout::GetFlex(nsIBox* aBox, nsBoxLayoutState& aState, nscoord& aFlex)
 {
-  return aBox->GetFlex(aState, aFlex);
+  aFlex = aBox->GetFlex(aState);
+  return NS_OK;
 }
 
 
 NS_IMETHODIMP
 nsBoxLayout::IsCollapsed(nsIBox* aBox, nsBoxLayoutState& aState, PRBool& aCollapsed)
 {
-  return aBox->IsCollapsed(aState, aCollapsed);
+  aCollapsed = aBox->IsCollapsed(aState);
+  return NS_OK;
 }
 
 NS_IMETHODIMP
diff --git a/mozilla/layout/xul/base/src/nsButtonBoxFrame.cpp b/mozilla/layout/xul/base/src/nsButtonBoxFrame.cpp
index d7266fd3de4..be3dab1baef 100644
--- a/mozilla/layout/xul/base/src/nsButtonBoxFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsButtonBoxFrame.cpp
@@ -63,13 +63,6 @@ NS_NewButtonBoxFrame (nsIPresShell* aPresShell, nsStyleContext* aContext)
   return new (aPresShell) nsButtonBoxFrame(aPresShell, aContext);
 } // NS_NewXULButtonFrame
 
-NS_IMETHODIMP
-nsButtonBoxFrame::GetMouseThrough(PRBool& aMouseThrough)
-{
-  aMouseThrough = PR_FALSE;
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsButtonBoxFrame::BuildDisplayListForChildren(nsDisplayListBuilder*   aBuilder,
                                               const nsRect&           aDirtyRect,
diff --git a/mozilla/layout/xul/base/src/nsButtonBoxFrame.h b/mozilla/layout/xul/base/src/nsButtonBoxFrame.h
index efc3f798b0a..023db51c590 100644
--- a/mozilla/layout/xul/base/src/nsButtonBoxFrame.h
+++ b/mozilla/layout/xul/base/src/nsButtonBoxFrame.h
@@ -56,7 +56,7 @@ public:
                                       nsGUIEvent* aEvent,
                                       nsEventStatus* aEventStatus);
 
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough);
+  virtual PRBool GetMouseThrough() const { return PR_FALSE; }
 
   virtual void MouseClicked (nsPresContext* aPresContext, nsGUIEvent* aEvent)
   { DoMouseClick(aEvent, PR_FALSE); }
diff --git a/mozilla/layout/xul/base/src/nsDeckFrame.cpp b/mozilla/layout/xul/base/src/nsDeckFrame.cpp
index b428fc6da1a..202cf0bc8c6 100644
--- a/mozilla/layout/xul/base/src/nsDeckFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsDeckFrame.cpp
@@ -80,16 +80,6 @@ nsDeckFrame::nsDeckFrame(nsIPresShell* aPresShell,
   SetLayoutManager(layout);
 }
 
-/**
- * Hack for deck who requires that all its children has widgets
- */
-NS_IMETHODIMP
-nsDeckFrame::ChildrenMustHaveWidgets(PRBool& aMust) const
-{
-  aMust = PR_TRUE;
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsDeckFrame::AttributeChanged(PRInt32         aNameSpaceID,
                               nsIAtom*        aAttribute,
diff --git a/mozilla/layout/xul/base/src/nsDeckFrame.h b/mozilla/layout/xul/base/src/nsDeckFrame.h
index 1399d254add..8397cb8f718 100644
--- a/mozilla/layout/xul/base/src/nsDeckFrame.h
+++ b/mozilla/layout/xul/base/src/nsDeckFrame.h
@@ -74,7 +74,7 @@ public:
                   nsIFrame*        aParent,
                   nsIFrame*        aPrevInFlow);
 
-  NS_IMETHOD ChildrenMustHaveWidgets(PRBool& aMust) const;
+  virtual PRBool ChildrenMustHaveWidgets() const { return PR_TRUE; }
 
 #ifdef NS_DEBUG
   NS_IMETHOD GetFrameName(nsAString& aResult) const
diff --git a/mozilla/layout/xul/base/src/nsLeafBoxFrame.cpp b/mozilla/layout/xul/base/src/nsLeafBoxFrame.cpp
index 931f70a9f3a..75838ec30ee 100644
--- a/mozilla/layout/xul/base/src/nsLeafBoxFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsLeafBoxFrame.cpp
@@ -100,9 +100,7 @@ nsLeafBoxFrame::Init(
 
    // see if we need a widget
   if (aParent && aParent->IsBoxFrame()) {
-    PRBool needsWidget = PR_FALSE;
-    aParent->ChildrenMustHaveWidgets(needsWidget);
-    if (needsWidget) {
+    if (aParent->ChildrenMustHaveWidgets()) {
         nsHTMLContainerFrame::CreateViewForFrame(this, nsnull, PR_TRUE); 
         nsIView* view = GetView();
 
@@ -146,29 +144,21 @@ void nsLeafBoxFrame::UpdateMouseThrough()
   }
 }
 
-NS_IMETHODIMP
-nsLeafBoxFrame::GetMouseThrough(PRBool& aMouseThrough)
+PRBool
+nsLeafBoxFrame::GetMouseThrough() const
 {
   switch (mMouseThrough)
   {
     case always:
-      aMouseThrough = PR_TRUE;
-      return NS_OK;
+      return PR_TRUE;
     case never:
-      aMouseThrough = PR_FALSE;      
-      return NS_OK;
+      return PR_FALSE;
     case unset:
-    {
       if (mParent && mParent->IsBoxFrame())
-        return mParent->GetMouseThrough(aMouseThrough);
-      else {
-        aMouseThrough = PR_FALSE;      
-        return NS_OK;
-      }
-    }
+        return mParent->GetMouseThrough();
   }
 
-  return NS_ERROR_FAILURE;
+  return PR_FALSE;
 }
 
 NS_IMETHODIMP
@@ -344,14 +334,9 @@ nsLeafBoxFrame::Reflow(nsPresContext*   aPresContext,
   Layout(state);
   
   // ok our child could have gotten bigger. So lets get its bounds
-  
-  // get the ascent
-  nscoord ascent = mRect.height;
-  GetAscent(state, ascent);
-
   aDesiredSize.width  = mRect.width;
   aDesiredSize.height = mRect.height;
-  aDesiredSize.ascent = ascent;
+  aDesiredSize.ascent = GetBoxAscent(state);
 
   // NS_FRAME_OUTSIDE_CHILDREN is set in SetBounds() above
   if (mState & NS_FRAME_OUTSIDE_CHILDREN) {
@@ -432,16 +417,16 @@ nsLeafBoxFrame::GetMaxSize(nsBoxLayoutState& aState)
     return nsBox::GetMaxSize(aState);
 }
 
-NS_IMETHODIMP
-nsLeafBoxFrame::GetFlex(nsBoxLayoutState& aState, nscoord& aFlex)
+/* virtual */ nscoord
+nsLeafBoxFrame::GetFlex(nsBoxLayoutState& aState)
 {
-    return nsBox::GetFlex(aState, aFlex);
+    return nsBox::GetFlex(aState);
 }
 
-NS_IMETHODIMP
-nsLeafBoxFrame::GetAscent(nsBoxLayoutState& aState, nscoord& aAscent)
+/* virtual */ nscoord
+nsLeafBoxFrame::GetBoxAscent(nsBoxLayoutState& aState)
 {
-    return nsBox::GetAscent(aState, aAscent);
+    return nsBox::GetBoxAscent(aState);
 }
 
 /* virtual */ void
diff --git a/mozilla/layout/xul/base/src/nsLeafBoxFrame.h b/mozilla/layout/xul/base/src/nsLeafBoxFrame.h
index 7b258832500..216b364fcb4 100644
--- a/mozilla/layout/xul/base/src/nsLeafBoxFrame.h
+++ b/mozilla/layout/xul/base/src/nsLeafBoxFrame.h
@@ -55,8 +55,8 @@ public:
   virtual nsSize GetPrefSize(nsBoxLayoutState& aState);
   virtual nsSize GetMinSize(nsBoxLayoutState& aState);
   virtual nsSize GetMaxSize(nsBoxLayoutState& aState);
-  NS_IMETHOD GetFlex(nsBoxLayoutState& aState, nscoord& aFlex);
-  NS_IMETHOD GetAscent(nsBoxLayoutState& aState, nscoord& aAscent);
+  virtual nscoord GetFlex(nsBoxLayoutState& aState);
+  virtual nscoord GetBoxAscent(nsBoxLayoutState& aState);
 
   virtual PRBool IsFrameOfType(PRUint32 aFlags) const;
 #ifdef DEBUG
@@ -91,7 +91,7 @@ public:
                               nsIAtom* aAttribute,
                               PRInt32 aModType);
 
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough);
+  virtual PRBool GetMouseThrough() const;
   virtual PRBool ComputesOwnOverflowArea() { return PR_FALSE; }
 
 protected:
diff --git a/mozilla/layout/xul/base/src/nsMenuFrame.cpp b/mozilla/layout/xul/base/src/nsMenuFrame.cpp
index 385c2e1723c..2f780df0e8f 100644
--- a/mozilla/layout/xul/base/src/nsMenuFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsMenuFrame.cpp
@@ -1031,9 +1031,6 @@ nsMenuFrame::GetMinSize(nsBoxLayoutState& aBoxLayoutState)
 NS_IMETHODIMP
 nsMenuFrame::DoLayout(nsBoxLayoutState& aState)
 {
-  nsRect contentRect;
-  GetContentRect(contentRect);
-
   // lay us out
   nsresult rv = nsBoxFrame::DoLayout(aState);
 
@@ -1053,7 +1050,7 @@ nsMenuFrame::DoLayout(nsBoxLayoutState& aState)
     BoundsCheck(minSize, prefSize, maxSize);
 
     if (sizeToPopup)
-        prefSize.width = contentRect.width;
+        prefSize.width = mRect.width;
 
     // if the pref size changed then set bounds to be the pref size
     // and sync the view. And set new pref size.
@@ -1952,10 +1949,8 @@ public:
   NS_IMETHOD Run() {
     nsIFrame* frame = mWeakFrame.GetFrame();
     if (frame) {
-      PRBool collapsed = PR_FALSE;
       nsBoxLayoutState state(frame->GetPresContext());
-      frame->IsCollapsed(state, collapsed);
-      if (!collapsed) {
+      if (!frame->IsCollapsed(state)) {
         nsIMenuFrame* imenu = nsnull;
         CallQueryInterface(frame, &imenu);
         if (imenu) {
@@ -1976,14 +1971,10 @@ public:
 PRBool
 nsMenuFrame::SizeToPopup(nsBoxLayoutState& aState, nsSize& aSize)
 {
-  PRBool collapsed = PR_FALSE;
-  IsCollapsed(aState, collapsed);
-  if (!collapsed) {
+  if (!IsCollapsed(aState)) {
     nsSize tmpSize(-1, 0);
     nsIBox::AddCSSPrefSize(aState, this, tmpSize);
-    nscoord flex;
-    GetFlex(aState, flex);
-    if (tmpSize.width == -1 && flex == 0) {
+    if (tmpSize.width == -1 && GetFlex(aState) == 0) {
       nsIFrame* frame = mPopupFrames.FirstChild();
       if (!frame) {
         nsCOMPtr<nsIContent> child;
diff --git a/mozilla/layout/xul/base/src/nsScrollBoxObject.cpp b/mozilla/layout/xul/base/src/nsScrollBoxObject.cpp
index ec2811b5c61..cfb6781b112 100644
--- a/mozilla/layout/xul/base/src/nsScrollBoxObject.cpp
+++ b/mozilla/layout/xul/base/src/nsScrollBoxObject.cpp
@@ -163,8 +163,7 @@ NS_IMETHODIMP nsScrollBoxObject::ScrollByIndex(PRInt32 dindexes)
     // now get the scrolled boxes first child.
     scrolledBox->GetChildBox(&child);
 
-    PRBool horiz = PR_FALSE;
-    scrolledBox->GetOrientation(horiz);
+    PRBool horiz = scrolledBox->IsHorizontal();
     nsPoint cp;
     scrollableView->GetScrollPosition(cp.x,cp.y);
     nscoord diff = 0;
@@ -303,8 +302,6 @@ NS_IMETHODIMP nsScrollBoxObject::ScrollToElement(nsIDOMElement *child)
     // TODO: make sure the child is inside the box
 
     // get our current info
-    PRBool horiz = PR_FALSE;
-    scrolledBox->GetOrientation(horiz);
     nsPoint cp;
     scrollableView->GetScrollPosition(cp.x,cp.y);
 
@@ -315,7 +312,7 @@ NS_IMETHODIMP nsScrollBoxObject::ScrollToElement(nsIDOMElement *child)
 
     // we only scroll in the direction of the scrollbox orientation
     // always scroll to left or top edge of child element
-    if (horiz) {
+    if (scrolledBox->IsHorizontal()) {
         newx = rect.x - crect.x;
     } else {
         newy = rect.y - crect.y;
@@ -429,9 +426,6 @@ NS_IMETHODIMP nsScrollBoxObject::EnsureElementIsVisible(nsIDOMElement *child)
     // TODO: make sure the child is inside the box
 
     // get our current info
-    PRBool horiz = PR_FALSE;
-    scrolledBox->GetOrientation(horiz);
-
     nsPoint cp;
     scrollableView->GetScrollPosition(cp.x,cp.y);
     GetOffsetRect(crect);    
@@ -440,11 +434,10 @@ NS_IMETHODIMP nsScrollBoxObject::EnsureElementIsVisible(nsIDOMElement *child)
     crect.width = NSToIntRound(crect.width * pixelsToTwips);
     crect.height = NSToIntRound(crect.height * pixelsToTwips);
 
-
     nscoord newx=cp.x, newy=cp.y;
 
     // we only scroll in the direction of the scrollbox orientation
-    if (horiz) {
+    if (scrolledBox->IsHorizontal()) {
         if ((rect.x - crect.x) + rect.width > cp.x + crect.width) {
             newx = cp.x + (((rect.x - crect.x) + rect.width)-(cp.x + crect.width));
         } else if (rect.x - crect.x < cp.x) {
diff --git a/mozilla/layout/xul/base/src/nsSliderFrame.cpp b/mozilla/layout/xul/base/src/nsSliderFrame.cpp
index 6cd9608ab29..b18f91e0145 100644
--- a/mozilla/layout/xul/base/src/nsSliderFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsSliderFrame.cpp
@@ -387,10 +387,7 @@ nsSliderFrame::DoLayout(nsBoxLayoutState& aState)
   if ((pageIncrement + maxpospx - minpospx) > 0)
   {
     // if the thumb is flexible make the thumb bigger.
-    nscoord flex = 0;
-    thumbBox->GetFlex(aState, flex);
-
-    if (flex > 0)
+    if (thumbBox->GetFlex(aState) > 0)
     {
       mRatio = float(pageIncrement) / float(maxpospx - minpospx + pageIncrement);
       nscoord thumbsize = NSToCoordRound(ourmaxpos * mRatio);
diff --git a/mozilla/layout/xul/base/src/nsSplitterFrame.cpp b/mozilla/layout/xul/base/src/nsSplitterFrame.cpp
index c73a5103fcf..3b3d189d521 100644
--- a/mozilla/layout/xul/base/src/nsSplitterFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsSplitterFrame.cpp
@@ -344,9 +344,7 @@ nsSplitterFrame::Init(nsIContent*      aContent,
   // |newContext| to Release the reference after the call to nsBoxFrame::Init
   nsRefPtr<nsStyleContext> newContext;
   if (aParent && aParent->IsBoxFrame()) {
-    PRBool isHorizontal;
-    aParent->GetOrientation(isHorizontal);
-    if (!isHorizontal) {
+    if (!aParent->IsHorizontal()) {
       if (!nsContentUtils::HasNonEmptyAttr(aContent, kNameSpaceID_None,
                                            nsGkAtoms::orient)) {
         aContent->SetAttr(kNameSpaceID_None, nsGkAtoms::orient,
@@ -400,9 +398,7 @@ nsSplitterFrame::GetInitialOrientation(PRBool& aIsHorizontal)
   nsIBox* box;
   GetParentBox(&box);
   if (box) {
-    PRBool horizontal;
-    box->GetOrientation(horizontal);
-    aIsHorizontal = !horizontal;
+    aIsHorizontal = !box->IsHorizontal();
   }
   else
     nsBoxFrame::GetInitialOrientation(aIsHorizontal);
@@ -784,8 +780,7 @@ nsSplitterFrameInner::MouseDown(nsIDOMEvent* aMouseEvent)
         mOuter->AddMargin(childBox, prefSize);
         mOuter->AddMargin(childBox, maxSize);
 
-        nscoord flex = 0;
-        childBox->GetFlex(state, flex);
+        nscoord flex = childBox->GetFlex(state);
 
         nsMargin margin(0,0,0,0);
         childBox->GetMargin(margin);
@@ -825,9 +820,7 @@ nsSplitterFrameInner::MouseDown(nsIDOMEvent* aMouseEvent)
     count++;
   }
 
-  PRBool isNormalDirection = PR_TRUE;
-  mParentBox->GetDirection(isNormalDirection);
-  if (!isNormalDirection) {
+  if (!mParentBox->IsNormalDirection()) {
     // The before array is really the after array, and the order needs to be reversed.
     // First reverse both arrays.
     Reverse(mChildInfosBefore, mChildInfosBeforeCount);
diff --git a/mozilla/layout/xul/base/src/nsSprocketLayout.cpp b/mozilla/layout/xul/base/src/nsSprocketLayout.cpp
index cd828ff6064..8b0ecd9def4 100644
--- a/mozilla/layout/xul/base/src/nsSprocketLayout.cpp
+++ b/mozilla/layout/xul/base/src/nsSprocketLayout.cpp
@@ -208,9 +208,7 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
 {
   // See if we are collapsed. If we are, then simply iterate over all our
   // children and give them a rect of 0 width and height.
-  PRBool collapsed = PR_FALSE;
-  aBox->IsCollapsed(aState, collapsed);
-  if (collapsed) {
+  if (aBox->IsCollapsed(aState)) {
     nsIBox* child;
     aBox->GetChildBox(&child);
     while(child) 
@@ -224,8 +222,7 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
   aState.PushStackMemory();
 
   // ----- figure out our size ----------
-  nsRect contentRect;
-  aBox->GetContentRect(contentRect);
+  nsSize originalSize = aBox->GetSize();
 
   // -- make sure we remove our border and padding  ----
   nsRect clientRect;
@@ -249,8 +246,7 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
   nsBoxSize*         boxSizes = nsnull;
   nsComputedBoxSize* computedBoxSizes = nsnull;
 
-  nscoord maxAscent = 0;
-  aBox->GetAscent(aState, maxAscent);
+  nscoord maxAscent = aBox->GetBoxAscent(aState);
 
   nscoord min = 0;
   nscoord max = 0;
@@ -663,14 +659,14 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
     aBox->GetInset(bp);
     tmpClientRect.Inflate(bp);
 
-    if (tmpClientRect.width > contentRect.width || tmpClientRect.height > contentRect.height)
+    if (tmpClientRect.width > originalSize.width || tmpClientRect.height > originalSize.height)
     {
       // if it did reset our bounds.
       nsRect bounds(aBox->GetRect());
-      if (tmpClientRect.width > contentRect.width)
+      if (tmpClientRect.width > originalSize.width)
         bounds.width = tmpClientRect.width;
 
-      if (tmpClientRect.height > contentRect.height)
+      if (tmpClientRect.height > originalSize.height)
         bounds.height = tmpClientRect.height;
 
       aBox->SetBounds(aState, bounds);
@@ -770,12 +766,10 @@ nsSprocketLayout::PopulateBoxSizes(nsIBox* aBox, nsBoxLayoutState& aState, nsBox
       }
     
 
-      child->GetFlex(aState, flex);
-      PRBool collapsed = PR_FALSE;    
-      child->IsCollapsed(aState, collapsed);
+      flex = child->GetFlex(aState);
 
       currentBox->flex = flex;
-      currentBox->collapsed = collapsed;
+      currentBox->collapsed = child->IsCollapsed(aState);
     } else {
       flex = start->flex;
       start = start->next;
@@ -803,9 +797,7 @@ nsSprocketLayout::PopulateBoxSizes(nsIBox* aBox, nsBoxLayoutState& aState, nsBox
     nsSize min(0,0);
     nsSize max(NS_INTRINSICSIZE,NS_INTRINSICSIZE);
     nscoord ascent = 0;
-
-    PRBool collapsed = PR_FALSE;    
-    child->IsCollapsed(aState, collapsed);
+    PRBool collapsed = child->IsCollapsed(aState);
 
     if (!collapsed) {
     // only one flexible child? Cool we will just make its preferred size
@@ -815,7 +807,7 @@ nsSprocketLayout::PopulateBoxSizes(nsIBox* aBox, nsBoxLayoutState& aState, nsBox
       pref = child->GetPrefSize(aState);
       min = child->GetMinSize(aState);
       max = child->GetMaxSize(aState);
-      child->GetAscent(aState, ascent);
+      ascent = child->GetBoxAscent(aState);
       nsMargin margin;
       child->GetMargin(margin);
       ascent += margin.top;
@@ -854,8 +846,7 @@ nsSprocketLayout::PopulateBoxSizes(nsIBox* aBox, nsBoxLayoutState& aState, nsBox
           prefWidth = pref.height;
       }
 
-      nscoord flex = 0;
-      child->GetFlex(aState, flex);
+      nscoord flex = child->GetFlex(aState);
 
       // set them if you collapsed you are not flexible.
       if (collapsed) {
@@ -1349,10 +1340,7 @@ nsSprocketLayout::GetPrefSize(nsIBox* aBox, nsBoxLayoutState& aState, nsSize& aS
    while (child) 
    {  
       // ignore collapsed children
-      PRBool isCollapsed = PR_FALSE;
-      child->IsCollapsed(aState, isCollapsed);
-
-      if (!isCollapsed)
+      if (!child->IsCollapsed(aState))
       {
         nsSize pref = child->GetPrefSize(aState);
         AddMargin(child, pref);
@@ -1412,20 +1400,14 @@ nsSprocketLayout::GetMinSize(nsIBox* aBox, nsBoxLayoutState& aState, nsSize& aSi
    while (child) 
    {  
        // ignore collapsed children
-      PRBool isCollapsed = PR_FALSE;
-      aBox->IsCollapsed(aState, isCollapsed);
-
-      if (!isCollapsed)
+      if (!aBox->IsCollapsed(aState))
       {
         nsSize min = child->GetMinSize(aState);
         nsSize pref(0,0);
-        nscoord flex = 0;
-
-        child->GetFlex(aState, flex);
         
         // if the child is not flexible then
         // its min size is its pref size.
-        if (flex == 0)  {
+        if (child->GetFlex(aState) == 0) {
             pref = child->GetPrefSize(aState);
             if (isHorizontal)
                min.width = pref.width;
@@ -1492,10 +1474,7 @@ nsSprocketLayout::GetMaxSize(nsIBox* aBox, nsBoxLayoutState& aState, nsSize& aSi
    while (child) 
    {  
       // ignore collapsed children
-      PRBool isCollapsed = PR_FALSE;
-      aBox->IsCollapsed(aState, isCollapsed);
-
-      if (!isCollapsed)
+      if (!aBox->IsCollapsed(aState))
       {
         // if completely redefined don't even ask our child for its size.
         nsSize max = child->GetMaxSize(aState);
@@ -1560,14 +1539,10 @@ nsSprocketLayout::GetAscent(nsIBox* aBox, nsBoxLayoutState& aState, nscoord& aAs
    while (child) 
    {  
       // ignore collapsed children
-      //PRBool isCollapsed = PR_FALSE;
-      //aBox->IsCollapsed(aState, isCollapsed);
-
-      //if (!isCollapsed)
+      //if (!aBox->IsCollapsed(aStatew))
       //{
         // if completely redefined don't even ask our child for its size.
-        nscoord ascent = 0;
-        child->GetAscent(aState, ascent);
+        nscoord ascent = child->GetBoxAscent(aState);
 
         nsMargin margin;
         child->GetMargin(margin);
@@ -1592,14 +1567,16 @@ nsSprocketLayout::GetAscent(nsIBox* aBox, nsBoxLayoutState& aState, nscoord& aAs
 NS_IMETHODIMP
 nsSprocketLayout::GetFlex(nsIBox* aBox, nsBoxLayoutState& aState, nscoord& aFlex)
 {
-  return aBox->GetFlex(aState, aFlex);
+  aFlex = aBox->GetFlex(aState);
+  return NS_OK;
 }
 
 
 NS_IMETHODIMP
 nsSprocketLayout::IsCollapsed(nsIBox* aBox, nsBoxLayoutState& aState, PRBool& aIsCollapsed)
 {
-  return aBox->IsCollapsed(aState, aIsCollapsed);
+  aIsCollapsed = aBox->IsCollapsed(aState);
+  return NS_OK;
 }
 
 void
diff --git a/mozilla/layout/xul/base/src/nsStackLayout.cpp b/mozilla/layout/xul/base/src/nsStackLayout.cpp
index 6b4fa126d00..b0d26619fbf 100644
--- a/mozilla/layout/xul/base/src/nsStackLayout.cpp
+++ b/mozilla/layout/xul/base/src/nsStackLayout.cpp
@@ -170,8 +170,7 @@ nsStackLayout::GetAscent(nsIBox* aBox, nsBoxLayoutState& aState, nscoord& aAscen
   aBox->GetChildBox(&child);
    
   while (child) {  
-    nscoord ascent = 0;
-    child->GetAscent(aState, ascent);
+    nscoord ascent = child->GetBoxAscent(aState);
     nsMargin margin;
     child->GetMargin(margin);
     ascent += margin.top + margin.bottom;
diff --git a/mozilla/layout/xul/base/src/nsTitleBarFrame.cpp b/mozilla/layout/xul/base/src/nsTitleBarFrame.cpp
index 703867b5772..8416b3ddd1e 100644
--- a/mozilla/layout/xul/base/src/nsTitleBarFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsTitleBarFrame.cpp
@@ -82,16 +82,6 @@ nsTitleBarFrame::Init(nsIContent*      aContent,
   return rv;
 }
 
-
-
-
-NS_IMETHODIMP
-nsTitleBarFrame::GetMouseThrough(PRBool& aMouseThrough)
-{
-  aMouseThrough = PR_FALSE;
-  return NS_OK;
-}
-
 NS_IMETHODIMP
 nsTitleBarFrame::BuildDisplayListForChildren(nsDisplayListBuilder*   aBuilder,
                                              const nsRect&           aDirtyRect,
diff --git a/mozilla/layout/xul/base/src/nsTitleBarFrame.h b/mozilla/layout/xul/base/src/nsTitleBarFrame.h
index 8bb2e56f809..01156ebd080 100644
--- a/mozilla/layout/xul/base/src/nsTitleBarFrame.h
+++ b/mozilla/layout/xul/base/src/nsTitleBarFrame.h
@@ -60,7 +60,7 @@ public:
                                       nsGUIEvent* aEvent,
                                       nsEventStatus* aEventStatus);
 
-  NS_IMETHOD GetMouseThrough(PRBool& aMouseThrough);
+  virtual PRBool GetMouseThrough() const { return PR_FALSE; }
 
   virtual void MouseClicked(nsPresContext* aPresContext, nsGUIEvent* aEvent);
 
diff --git a/mozilla/layout/xul/base/src/tree/src/nsTreeBodyFrame.cpp b/mozilla/layout/xul/base/src/tree/src/nsTreeBodyFrame.cpp
index deb4766849e..28d3ac4e912 100644
--- a/mozilla/layout/xul/base/src/tree/src/nsTreeBodyFrame.cpp
+++ b/mozilla/layout/xul/base/src/tree/src/nsTreeBodyFrame.cpp
@@ -759,16 +759,13 @@ FindScrollParts(nsIFrame* aCurrFrame, nsTreeBodyFrame::ScrollParts* aResult)
   nsIScrollbarFrame *sf = nsnull;
   CallQueryInterface(aCurrFrame, &sf);
   if (sf) {
-    PRBool isHorizontal = PR_FALSE;
-    if (NS_SUCCEEDED(aCurrFrame->GetOrientation(isHorizontal))) {
-      if (!isHorizontal) {
-        if (!aResult->mVScrollbar) {
-          aResult->mVScrollbar = sf;
-        }
-      } else {
-        if (!aResult->mHScrollbar) {
-          aResult->mHScrollbar = sf;
-        }
+    if (!aCurrFrame->IsHorizontal()) {
+      if (!aResult->mVScrollbar) {
+        aResult->mVScrollbar = sf;
+      }
+    } else {
+      if (!aResult->mHScrollbar) {
+        aResult->mHScrollbar = sf;
       }
     }
     // don't bother searching inside a scrollbar