diff --git a/mozilla/content/html/content/src/nsGenericHTMLElement.cpp b/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
index be392664932..cd9c06c56e9 100644
--- a/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
+++ b/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
@@ -3035,7 +3035,7 @@ nsGenericHTMLElement::MapScrollingAttributeInto(const nsMappedAttributes* aAttri
         case NS_STYLE_FRAME_OFF:
         case NS_STYLE_FRAME_NOSCROLL:
         case NS_STYLE_FRAME_NO:
-          mappedValue = NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+          mappedValue = NS_STYLE_OVERFLOW_HIDDEN;
           break;
       
         case NS_STYLE_FRAME_AUTO:
diff --git a/mozilla/content/shared/src/nsCSSProps.cpp b/mozilla/content/shared/src/nsCSSProps.cpp
index c033f43b656..e90497b114c 100644
--- a/mozilla/content/shared/src/nsCSSProps.cpp
+++ b/mozilla/content/shared/src/nsCSSProps.cpp
@@ -677,12 +677,12 @@ const PRInt32 nsCSSProps::kOutlineColorKTable[] = {
 
 const PRInt32 nsCSSProps::kOverflowKTable[] = {
   eCSSKeyword_visible, NS_STYLE_OVERFLOW_VISIBLE,
-  eCSSKeyword_hidden, NS_STYLE_OVERFLOW_SCROLLBARS_NONE,
+  eCSSKeyword_hidden, NS_STYLE_OVERFLOW_HIDDEN,
   eCSSKeyword_scroll, NS_STYLE_OVERFLOW_SCROLL,
-  eCSSKeyword__moz_scrollbars_none, NS_STYLE_OVERFLOW_SCROLLBARS_NONE,
+  eCSSKeyword__moz_scrollbars_none, NS_STYLE_OVERFLOW_HIDDEN,
   eCSSKeyword__moz_scrollbars_horizontal, NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL,
   eCSSKeyword__moz_scrollbars_vertical, NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL,
-  eCSSKeyword__moz_hidden_unscrollable, NS_STYLE_OVERFLOW_HIDDEN,
+  eCSSKeyword__moz_hidden_unscrollable, NS_STYLE_OVERFLOW_CLIP,
   -1,-1
 };
 
diff --git a/mozilla/layout/base/nsCSSFrameConstructor.cpp b/mozilla/layout/base/nsCSSFrameConstructor.cpp
index 5ed161fe0af..cd14b9df8c5 100644
--- a/mozilla/layout/base/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/base/nsCSSFrameConstructor.cpp
@@ -6552,7 +6552,7 @@ nsCSSFrameConstructor::IsScrollable(nsPresContext*       aPresContext,
   switch (aDisplay->mOverflow) {
   	case NS_STYLE_OVERFLOW_SCROLL:
   	case NS_STYLE_OVERFLOW_AUTO:
-  	case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
+  	case NS_STYLE_OVERFLOW_HIDDEN:
   	case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
   	case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
 	    return PR_TRUE;
diff --git a/mozilla/layout/base/nsStyleConsts.h b/mozilla/layout/base/nsStyleConsts.h
index 696c65a6753..de7115ac6a6 100644
--- a/mozilla/layout/base/nsStyleConsts.h
+++ b/mozilla/layout/base/nsStyleConsts.h
@@ -441,9 +441,9 @@
 #define NS_STYLE_OVERFLOW_HIDDEN                1
 #define NS_STYLE_OVERFLOW_SCROLL                2
 #define NS_STYLE_OVERFLOW_AUTO                  3
-#define NS_STYLE_OVERFLOW_SCROLLBARS_NONE				4
-#define NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL	5
-#define NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL		6
+#define NS_STYLE_OVERFLOW_CLIP                  4
+#define NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL 5
+#define NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL   6
 
 // See nsStyleList
 #define NS_STYLE_LIST_STYLE_NONE                  0
diff --git a/mozilla/layout/base/public/nsStyleConsts.h b/mozilla/layout/base/public/nsStyleConsts.h
index 696c65a6753..de7115ac6a6 100644
--- a/mozilla/layout/base/public/nsStyleConsts.h
+++ b/mozilla/layout/base/public/nsStyleConsts.h
@@ -441,9 +441,9 @@
 #define NS_STYLE_OVERFLOW_HIDDEN                1
 #define NS_STYLE_OVERFLOW_SCROLL                2
 #define NS_STYLE_OVERFLOW_AUTO                  3
-#define NS_STYLE_OVERFLOW_SCROLLBARS_NONE				4
-#define NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL	5
-#define NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL		6
+#define NS_STYLE_OVERFLOW_CLIP                  4
+#define NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL 5
+#define NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL   6
 
 // See nsStyleList
 #define NS_STYLE_LIST_STYLE_NONE                  0
diff --git a/mozilla/layout/forms/nsTextControlFrame.cpp b/mozilla/layout/forms/nsTextControlFrame.cpp
index d5b890bfe4e..49597e02be4 100644
--- a/mozilla/layout/forms/nsTextControlFrame.cpp
+++ b/mozilla/layout/forms/nsTextControlFrame.cpp
@@ -1634,12 +1634,12 @@ nsTextControlFrame::CreateAnonymousContent(nsPresContext* aPresContext,
   if (!IsSingleLineTextControl()) {
     // We can't just inherit the overflow because setting visible overflow will
     // crash when the number of lines exceeds the height of the textarea and
-    // setting -moz-hidden-unscrollable overflow (NS_STYLE_OVERFLOW_HIDDEN)
+    // setting -moz-hidden-unscrollable overflow (NS_STYLE_OVERFLOW_CLIP)
     // doesn't paint the caret for some reason.
     const nsStyleDisplay* disp = GetStyleDisplay();
     if (disp->mOverflow != NS_STYLE_OVERFLOW_AUTO &&  // this is the default
         disp->mOverflow != NS_STYLE_OVERFLOW_VISIBLE &&
-        disp->mOverflow != NS_STYLE_OVERFLOW_HIDDEN) {
+        disp->mOverflow != NS_STYLE_OVERFLOW_CLIP) {
       rv = divContent->SetAttr(kNameSpaceID_None, nsHTMLAtoms::style,
                                NS_LITERAL_STRING("overflow: inherit;"),
                                PR_FALSE);
diff --git a/mozilla/layout/generic/nsBlockFrame.cpp b/mozilla/layout/generic/nsBlockFrame.cpp
index b5218e5c430..3d9ceb86eb9 100644
--- a/mozilla/layout/generic/nsBlockFrame.cpp
+++ b/mozilla/layout/generic/nsBlockFrame.cpp
@@ -900,7 +900,7 @@ nsBlockFrame::Reflow(nsPresContext*          aPresContext,
   }
 
   if (NS_FRAME_IS_NOT_COMPLETE(state.mReflowStatus)) {
-    if (NS_STYLE_OVERFLOW_HIDDEN == aReflowState.mStyleDisplay->mOverflow) {
+    if (NS_STYLE_OVERFLOW_CLIP == aReflowState.mStyleDisplay->mOverflow) {
       state.mReflowStatus = NS_FRAME_COMPLETE;
     }
     else {
@@ -1373,7 +1373,7 @@ nsBlockFrame::ComputeCombinedArea(const nsHTMLReflowState& aReflowState,
   // XXX_perf: This can be done incrementally.  It is currently one of
   // the things that makes incremental reflow O(N^2).
   nscoord xa = 0, ya = 0, xb = aMetrics.width, yb = aMetrics.height;
-  if (NS_STYLE_OVERFLOW_HIDDEN != aReflowState.mStyleDisplay->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != aReflowState.mStyleDisplay->mOverflow) {
     for (line_iterator line = begin_lines(), line_end = end_lines();
          line != line_end;
          ++line)
@@ -5257,7 +5257,7 @@ nsBlockFrame::Paint(nsPresContext*      aPresContext,
   // If overflow is hidden then set the clip rect so that children don't
   // leak out of us. Note that because overflow'-clip' only applies to
   // the content area we do this after painting the border and background
-  if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
   }
@@ -5271,7 +5271,7 @@ nsBlockFrame::Paint(nsPresContext*      aPresContext,
   PaintDecorationsAndChildren(aPresContext, aRenderingContext,
                               aDirtyRect, aWhichLayer, PR_TRUE);
 
-  if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow)
+  if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow)
     aRenderingContext.PopState();
 
 #if 0
diff --git a/mozilla/layout/generic/nsContainerFrame.cpp b/mozilla/layout/generic/nsContainerFrame.cpp
index bfbc5b4632e..79f510e54c4 100644
--- a/mozilla/layout/generic/nsContainerFrame.cpp
+++ b/mozilla/layout/generic/nsContainerFrame.cpp
@@ -657,7 +657,7 @@ SyncFrameViewGeometryDependentProperties(nsPresContext*  aPresContext,
   //   in the style context...
   PRBool isBlockLevel = display->IsBlockLevel() || (kidState & NS_FRAME_OUT_OF_FLOW);
   PRBool hasClip = display->IsAbsolutelyPositioned() && (display->mClipFlags & NS_STYLE_CLIP_RECT);
-  PRBool hasOverflowClip = isBlockLevel && (display->mOverflow == NS_STYLE_OVERFLOW_HIDDEN);
+  PRBool hasOverflowClip = isBlockLevel && (display->mOverflow == NS_STYLE_OVERFLOW_CLIP);
   if (hasClip || hasOverflowClip) {
     nsSize frameSize = aFrame->GetSize();
     nsRect  clipRect;
@@ -908,7 +908,7 @@ nsContainerFrame::FrameNeedsView(nsIFrame* aFrame)
   // block-level, but we can't trust that the style context 'display' value is
   // set correctly
   if ((display->IsBlockLevel() || display->IsFloating()) &&
-      (display->mOverflow == NS_STYLE_OVERFLOW_HIDDEN)) {
+      (display->mOverflow == NS_STYLE_OVERFLOW_CLIP)) {
     // XXX Check for the frame being a block frame and only force a view
     // in that case, because adding a view for box frames seems to cause
     // problems for XUL...
diff --git a/mozilla/layout/generic/nsFrame.cpp b/mozilla/layout/generic/nsFrame.cpp
index fb7c43630bb..ed9fcce34cc 100644
--- a/mozilla/layout/generic/nsFrame.cpp
+++ b/mozilla/layout/generic/nsFrame.cpp
@@ -4284,10 +4284,10 @@ nsFrame::ConsiderChildOverflow(nsPresContext* aPresContext,
                                nsIFrame*       aChildFrame)
 {
   const nsStyleDisplay* disp = GetStyleDisplay();
-  // check here also for scrollbar none as table frames (table, tr and td) currently 
+  // check here also for hidden as table frames (table, tr and td) currently 
   // don't wrap their content into a scrollable frame if overflow is specified
-  if (NS_STYLE_OVERFLOW_HIDDEN != disp->mOverflow &&
-      NS_STYLE_OVERFLOW_SCROLLBARS_NONE != disp->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != disp->mOverflow &&
+      NS_STYLE_OVERFLOW_HIDDEN != disp->mOverflow) {
     nsRect* overflowArea = aChildFrame->GetOverflowAreaProperty();
     if (overflowArea) {
       nsRect childOverflow(*overflowArea);
diff --git a/mozilla/layout/generic/nsFrameFrame.cpp b/mozilla/layout/generic/nsFrameFrame.cpp
index aeb86ac0aab..c4a2764c12d 100644
--- a/mozilla/layout/generic/nsFrameFrame.cpp
+++ b/mozilla/layout/generic/nsFrameFrame.cpp
@@ -649,7 +649,7 @@ nsSubDocumentFrame::ShowDocShell()
     PRInt32 scrolling = GetStyleDisplay()->mOverflow;
     PRInt32 scrollX, scrollY;
     switch (scrolling) {
-      case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
+      case NS_STYLE_OVERFLOW_CLIP:
         scrollX = NS_STYLE_OVERFLOW_HIDDEN;
         scrollY = NS_STYLE_OVERFLOW_HIDDEN;
         break;
diff --git a/mozilla/layout/generic/nsGfxScrollFrame.cpp b/mozilla/layout/generic/nsGfxScrollFrame.cpp
index a2d5f946d78..c33f6f3272c 100644
--- a/mozilla/layout/generic/nsGfxScrollFrame.cpp
+++ b/mozilla/layout/generic/nsGfxScrollFrame.cpp
@@ -1205,12 +1205,14 @@ nsGfxScrollFrameInner::GetScrollbarStylesFromFrame() const
   switch (overflow) {
   case NS_STYLE_OVERFLOW_SCROLL:
   case NS_STYLE_OVERFLOW_HIDDEN:
-  case NS_STYLE_OVERFLOW_VISIBLE:
+  case NS_STYLE_OVERFLOW_VISIBLE: // should never happen
   case NS_STYLE_OVERFLOW_AUTO:
     return ScrollbarStyles(overflow, overflow);
-  case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
-    // This isn't quite right. The scrollframe will still be scrollable using keys.
-    // This can happen when HTML or BODY has propagated this style to the viewport.
+  case NS_STYLE_OVERFLOW_CLIP:
+    // This isn't quite right (although the value is deprecated and not
+    // very important). The scrollframe will still be scrollable using
+    // keys.  This can happen when HTML or BODY has propagated the style
+    // to the viewport.  (In other cases, there will be no scrollframe.)
     return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN);
   case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
     return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_SCROLL);
diff --git a/mozilla/layout/html/base/src/nsBlockFrame.cpp b/mozilla/layout/html/base/src/nsBlockFrame.cpp
index b5218e5c430..3d9ceb86eb9 100644
--- a/mozilla/layout/html/base/src/nsBlockFrame.cpp
+++ b/mozilla/layout/html/base/src/nsBlockFrame.cpp
@@ -900,7 +900,7 @@ nsBlockFrame::Reflow(nsPresContext*          aPresContext,
   }
 
   if (NS_FRAME_IS_NOT_COMPLETE(state.mReflowStatus)) {
-    if (NS_STYLE_OVERFLOW_HIDDEN == aReflowState.mStyleDisplay->mOverflow) {
+    if (NS_STYLE_OVERFLOW_CLIP == aReflowState.mStyleDisplay->mOverflow) {
       state.mReflowStatus = NS_FRAME_COMPLETE;
     }
     else {
@@ -1373,7 +1373,7 @@ nsBlockFrame::ComputeCombinedArea(const nsHTMLReflowState& aReflowState,
   // XXX_perf: This can be done incrementally.  It is currently one of
   // the things that makes incremental reflow O(N^2).
   nscoord xa = 0, ya = 0, xb = aMetrics.width, yb = aMetrics.height;
-  if (NS_STYLE_OVERFLOW_HIDDEN != aReflowState.mStyleDisplay->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != aReflowState.mStyleDisplay->mOverflow) {
     for (line_iterator line = begin_lines(), line_end = end_lines();
          line != line_end;
          ++line)
@@ -5257,7 +5257,7 @@ nsBlockFrame::Paint(nsPresContext*      aPresContext,
   // If overflow is hidden then set the clip rect so that children don't
   // leak out of us. Note that because overflow'-clip' only applies to
   // the content area we do this after painting the border and background
-  if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
   }
@@ -5271,7 +5271,7 @@ nsBlockFrame::Paint(nsPresContext*      aPresContext,
   PaintDecorationsAndChildren(aPresContext, aRenderingContext,
                               aDirtyRect, aWhichLayer, PR_TRUE);
 
-  if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow)
+  if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow)
     aRenderingContext.PopState();
 
 #if 0
diff --git a/mozilla/layout/html/base/src/nsContainerFrame.cpp b/mozilla/layout/html/base/src/nsContainerFrame.cpp
index bfbc5b4632e..79f510e54c4 100644
--- a/mozilla/layout/html/base/src/nsContainerFrame.cpp
+++ b/mozilla/layout/html/base/src/nsContainerFrame.cpp
@@ -657,7 +657,7 @@ SyncFrameViewGeometryDependentProperties(nsPresContext*  aPresContext,
   //   in the style context...
   PRBool isBlockLevel = display->IsBlockLevel() || (kidState & NS_FRAME_OUT_OF_FLOW);
   PRBool hasClip = display->IsAbsolutelyPositioned() && (display->mClipFlags & NS_STYLE_CLIP_RECT);
-  PRBool hasOverflowClip = isBlockLevel && (display->mOverflow == NS_STYLE_OVERFLOW_HIDDEN);
+  PRBool hasOverflowClip = isBlockLevel && (display->mOverflow == NS_STYLE_OVERFLOW_CLIP);
   if (hasClip || hasOverflowClip) {
     nsSize frameSize = aFrame->GetSize();
     nsRect  clipRect;
@@ -908,7 +908,7 @@ nsContainerFrame::FrameNeedsView(nsIFrame* aFrame)
   // block-level, but we can't trust that the style context 'display' value is
   // set correctly
   if ((display->IsBlockLevel() || display->IsFloating()) &&
-      (display->mOverflow == NS_STYLE_OVERFLOW_HIDDEN)) {
+      (display->mOverflow == NS_STYLE_OVERFLOW_CLIP)) {
     // XXX Check for the frame being a block frame and only force a view
     // in that case, because adding a view for box frames seems to cause
     // problems for XUL...
diff --git a/mozilla/layout/html/base/src/nsFrame.cpp b/mozilla/layout/html/base/src/nsFrame.cpp
index fb7c43630bb..ed9fcce34cc 100644
--- a/mozilla/layout/html/base/src/nsFrame.cpp
+++ b/mozilla/layout/html/base/src/nsFrame.cpp
@@ -4284,10 +4284,10 @@ nsFrame::ConsiderChildOverflow(nsPresContext* aPresContext,
                                nsIFrame*       aChildFrame)
 {
   const nsStyleDisplay* disp = GetStyleDisplay();
-  // check here also for scrollbar none as table frames (table, tr and td) currently 
+  // check here also for hidden as table frames (table, tr and td) currently 
   // don't wrap their content into a scrollable frame if overflow is specified
-  if (NS_STYLE_OVERFLOW_HIDDEN != disp->mOverflow &&
-      NS_STYLE_OVERFLOW_SCROLLBARS_NONE != disp->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != disp->mOverflow &&
+      NS_STYLE_OVERFLOW_HIDDEN != disp->mOverflow) {
     nsRect* overflowArea = aChildFrame->GetOverflowAreaProperty();
     if (overflowArea) {
       nsRect childOverflow(*overflowArea);
diff --git a/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp b/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
index a2d5f946d78..c33f6f3272c 100644
--- a/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
+++ b/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
@@ -1205,12 +1205,14 @@ nsGfxScrollFrameInner::GetScrollbarStylesFromFrame() const
   switch (overflow) {
   case NS_STYLE_OVERFLOW_SCROLL:
   case NS_STYLE_OVERFLOW_HIDDEN:
-  case NS_STYLE_OVERFLOW_VISIBLE:
+  case NS_STYLE_OVERFLOW_VISIBLE: // should never happen
   case NS_STYLE_OVERFLOW_AUTO:
     return ScrollbarStyles(overflow, overflow);
-  case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
-    // This isn't quite right. The scrollframe will still be scrollable using keys.
-    // This can happen when HTML or BODY has propagated this style to the viewport.
+  case NS_STYLE_OVERFLOW_CLIP:
+    // This isn't quite right (although the value is deprecated and not
+    // very important). The scrollframe will still be scrollable using
+    // keys.  This can happen when HTML or BODY has propagated the style
+    // to the viewport.  (In other cases, there will be no scrollframe.)
     return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN);
   case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
     return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_SCROLL);
diff --git a/mozilla/layout/html/document/src/nsFrameFrame.cpp b/mozilla/layout/html/document/src/nsFrameFrame.cpp
index aeb86ac0aab..c4a2764c12d 100644
--- a/mozilla/layout/html/document/src/nsFrameFrame.cpp
+++ b/mozilla/layout/html/document/src/nsFrameFrame.cpp
@@ -649,7 +649,7 @@ nsSubDocumentFrame::ShowDocShell()
     PRInt32 scrolling = GetStyleDisplay()->mOverflow;
     PRInt32 scrollX, scrollY;
     switch (scrolling) {
-      case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
+      case NS_STYLE_OVERFLOW_CLIP:
         scrollX = NS_STYLE_OVERFLOW_HIDDEN;
         scrollY = NS_STYLE_OVERFLOW_HIDDEN;
         break;
diff --git a/mozilla/layout/html/forms/src/nsTextControlFrame.cpp b/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
index d5b890bfe4e..49597e02be4 100644
--- a/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
+++ b/mozilla/layout/html/forms/src/nsTextControlFrame.cpp
@@ -1634,12 +1634,12 @@ nsTextControlFrame::CreateAnonymousContent(nsPresContext* aPresContext,
   if (!IsSingleLineTextControl()) {
     // We can't just inherit the overflow because setting visible overflow will
     // crash when the number of lines exceeds the height of the textarea and
-    // setting -moz-hidden-unscrollable overflow (NS_STYLE_OVERFLOW_HIDDEN)
+    // setting -moz-hidden-unscrollable overflow (NS_STYLE_OVERFLOW_CLIP)
     // doesn't paint the caret for some reason.
     const nsStyleDisplay* disp = GetStyleDisplay();
     if (disp->mOverflow != NS_STYLE_OVERFLOW_AUTO &&  // this is the default
         disp->mOverflow != NS_STYLE_OVERFLOW_VISIBLE &&
-        disp->mOverflow != NS_STYLE_OVERFLOW_HIDDEN) {
+        disp->mOverflow != NS_STYLE_OVERFLOW_CLIP) {
       rv = divContent->SetAttr(kNameSpaceID_None, nsHTMLAtoms::style,
                                NS_LITERAL_STRING("overflow: inherit;"),
                                PR_FALSE);
diff --git a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
index 5ed161fe0af..cd14b9df8c5 100644
--- a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
@@ -6552,7 +6552,7 @@ nsCSSFrameConstructor::IsScrollable(nsPresContext*       aPresContext,
   switch (aDisplay->mOverflow) {
   	case NS_STYLE_OVERFLOW_SCROLL:
   	case NS_STYLE_OVERFLOW_AUTO:
-  	case NS_STYLE_OVERFLOW_SCROLLBARS_NONE:
+  	case NS_STYLE_OVERFLOW_HIDDEN:
   	case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
   	case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
 	    return PR_TRUE;
diff --git a/mozilla/layout/html/table/src/nsTableCellFrame.cpp b/mozilla/layout/html/table/src/nsTableCellFrame.cpp
index 61c8fe1bed3..7f06c9be5d3 100644
--- a/mozilla/layout/html/table/src/nsTableCellFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableCellFrame.cpp
@@ -432,10 +432,10 @@ nsTableCellFrame::Paint(nsPresContext*      aPresContext,
                                     nsClipCombine_kIntersect);
     }
     else {
-      if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow ||
-          // XXXldb SCROLLBARS_NONE should really create a scrollframe,
+      if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow ||
+          // XXXldb HIDDEN should really create a scrollframe,
           // but test here since it doesn't.
-          NS_STYLE_OVERFLOW_SCROLLBARS_NONE == disp->mOverflow ||
+          NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow ||
           HasPctOverHeight()) {
         aRenderingContext.PushState();
         pushed = PR_TRUE;
diff --git a/mozilla/layout/html/table/src/nsTableFrame.cpp b/mozilla/layout/html/table/src/nsTableFrame.cpp
index 80349d8ab9e..c2b71791795 100644
--- a/mozilla/layout/html/table/src/nsTableFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableFrame.cpp
@@ -1363,8 +1363,8 @@ nsTableFrame::PaintChildren(nsPresContext*      aPresContext,
 
 {
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   // If overflow is hidden then set the clip rect so that children don't
   // leak out of us. Note that because overflow'-clip' only applies to
   // the content area we do this after painting the border and background
@@ -2076,7 +2076,7 @@ NS_METHOD nsTableFrame::Reflow(nsPresContext*          aPresContext,
   if (aDesiredSize.mFlags & NS_REFLOW_CALC_MAX_WIDTH) {
     aDesiredSize.mMaximumWidth = GetPreferredWidth();
   }
-  if (NS_STYLE_OVERFLOW_HIDDEN != aReflowState.mStyleDisplay->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != aReflowState.mStyleDisplay->mOverflow) {
     // collapsed border may leak out
     nsMargin bcMargin = GetBCMargin(aPresContext);
     nsRect tableRect(0, 0, aDesiredSize.width, aDesiredSize.height) ;
diff --git a/mozilla/layout/html/table/src/nsTableOuterFrame.cpp b/mozilla/layout/html/table/src/nsTableOuterFrame.cpp
index c0a8227f641..127772f39a6 100644
--- a/mozilla/layout/html/table/src/nsTableOuterFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableOuterFrame.cpp
@@ -334,8 +334,8 @@ nsTableOuterFrame::Paint(nsPresContext*      aPresContext,
   // If overflow is hidden then set the clip rect so that children
   // don't leak out of us
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   if (clip) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
diff --git a/mozilla/layout/html/table/src/nsTableRowFrame.cpp b/mozilla/layout/html/table/src/nsTableRowFrame.cpp
index a7fe09982ce..ddc21633fbf 100644
--- a/mozilla/layout/html/table/src/nsTableRowFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableRowFrame.cpp
@@ -556,8 +556,8 @@ NS_METHOD nsTableRowFrame::Paint(nsPresContext*      aPresContext,
   }
 
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   if (clip) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
diff --git a/mozilla/layout/style/nsCSSProps.cpp b/mozilla/layout/style/nsCSSProps.cpp
index c033f43b656..e90497b114c 100644
--- a/mozilla/layout/style/nsCSSProps.cpp
+++ b/mozilla/layout/style/nsCSSProps.cpp
@@ -677,12 +677,12 @@ const PRInt32 nsCSSProps::kOutlineColorKTable[] = {
 
 const PRInt32 nsCSSProps::kOverflowKTable[] = {
   eCSSKeyword_visible, NS_STYLE_OVERFLOW_VISIBLE,
-  eCSSKeyword_hidden, NS_STYLE_OVERFLOW_SCROLLBARS_NONE,
+  eCSSKeyword_hidden, NS_STYLE_OVERFLOW_HIDDEN,
   eCSSKeyword_scroll, NS_STYLE_OVERFLOW_SCROLL,
-  eCSSKeyword__moz_scrollbars_none, NS_STYLE_OVERFLOW_SCROLLBARS_NONE,
+  eCSSKeyword__moz_scrollbars_none, NS_STYLE_OVERFLOW_HIDDEN,
   eCSSKeyword__moz_scrollbars_horizontal, NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL,
   eCSSKeyword__moz_scrollbars_vertical, NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL,
-  eCSSKeyword__moz_hidden_unscrollable, NS_STYLE_OVERFLOW_HIDDEN,
+  eCSSKeyword__moz_hidden_unscrollable, NS_STYLE_OVERFLOW_CLIP,
   -1,-1
 };
 
diff --git a/mozilla/layout/tables/nsTableCellFrame.cpp b/mozilla/layout/tables/nsTableCellFrame.cpp
index 61c8fe1bed3..7f06c9be5d3 100644
--- a/mozilla/layout/tables/nsTableCellFrame.cpp
+++ b/mozilla/layout/tables/nsTableCellFrame.cpp
@@ -432,10 +432,10 @@ nsTableCellFrame::Paint(nsPresContext*      aPresContext,
                                     nsClipCombine_kIntersect);
     }
     else {
-      if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow ||
-          // XXXldb SCROLLBARS_NONE should really create a scrollframe,
+      if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow ||
+          // XXXldb HIDDEN should really create a scrollframe,
           // but test here since it doesn't.
-          NS_STYLE_OVERFLOW_SCROLLBARS_NONE == disp->mOverflow ||
+          NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow ||
           HasPctOverHeight()) {
         aRenderingContext.PushState();
         pushed = PR_TRUE;
diff --git a/mozilla/layout/tables/nsTableFrame.cpp b/mozilla/layout/tables/nsTableFrame.cpp
index 80349d8ab9e..c2b71791795 100644
--- a/mozilla/layout/tables/nsTableFrame.cpp
+++ b/mozilla/layout/tables/nsTableFrame.cpp
@@ -1363,8 +1363,8 @@ nsTableFrame::PaintChildren(nsPresContext*      aPresContext,
 
 {
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   // If overflow is hidden then set the clip rect so that children don't
   // leak out of us. Note that because overflow'-clip' only applies to
   // the content area we do this after painting the border and background
@@ -2076,7 +2076,7 @@ NS_METHOD nsTableFrame::Reflow(nsPresContext*          aPresContext,
   if (aDesiredSize.mFlags & NS_REFLOW_CALC_MAX_WIDTH) {
     aDesiredSize.mMaximumWidth = GetPreferredWidth();
   }
-  if (NS_STYLE_OVERFLOW_HIDDEN != aReflowState.mStyleDisplay->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP != aReflowState.mStyleDisplay->mOverflow) {
     // collapsed border may leak out
     nsMargin bcMargin = GetBCMargin(aPresContext);
     nsRect tableRect(0, 0, aDesiredSize.width, aDesiredSize.height) ;
diff --git a/mozilla/layout/tables/nsTableOuterFrame.cpp b/mozilla/layout/tables/nsTableOuterFrame.cpp
index c0a8227f641..127772f39a6 100644
--- a/mozilla/layout/tables/nsTableOuterFrame.cpp
+++ b/mozilla/layout/tables/nsTableOuterFrame.cpp
@@ -334,8 +334,8 @@ nsTableOuterFrame::Paint(nsPresContext*      aPresContext,
   // If overflow is hidden then set the clip rect so that children
   // don't leak out of us
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   if (clip) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
diff --git a/mozilla/layout/tables/nsTableRowFrame.cpp b/mozilla/layout/tables/nsTableRowFrame.cpp
index a7fe09982ce..ddc21633fbf 100644
--- a/mozilla/layout/tables/nsTableRowFrame.cpp
+++ b/mozilla/layout/tables/nsTableRowFrame.cpp
@@ -556,8 +556,8 @@ NS_METHOD nsTableRowFrame::Paint(nsPresContext*      aPresContext,
   }
 
   PRUint8 overflow = GetStyleDisplay()->mOverflow;
-  PRBool clip = overflow == NS_STYLE_OVERFLOW_HIDDEN ||
-                overflow == NS_STYLE_OVERFLOW_SCROLLBARS_NONE;
+  PRBool clip = overflow == NS_STYLE_OVERFLOW_CLIP ||
+                overflow == NS_STYLE_OVERFLOW_HIDDEN;
   if (clip) {
     aRenderingContext.PushState();
     SetOverflowClipRect(aRenderingContext);
diff --git a/mozilla/layout/xul/base/src/nsBoxFrame.cpp b/mozilla/layout/xul/base/src/nsBoxFrame.cpp
index 2995412631e..dbc59dcc17a 100644
--- a/mozilla/layout/xul/base/src/nsBoxFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsBoxFrame.cpp
@@ -1632,7 +1632,7 @@ nsBoxFrame::PaintChildren(nsPresContext*      aPresContext,
   
   // If overflow is hidden then set the clip rect so that children
   // don't leak out of us
-  if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+  if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
     nsMargin im(0,0,0,0);
     GetInset(im);
     r.Deflate(im);
@@ -1645,7 +1645,7 @@ nsBoxFrame::PaintChildren(nsPresContext*      aPresContext,
     nsIFrame* frame = nsnull;
     kid->GetFrame(&frame);
 
-    if (!hasClipped && NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+    if (!hasClipped && NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
         // if we haven't already clipped and we should
         // check to see if the child is in out bounds. If not then
         // we begin clipping.
@@ -1674,7 +1674,7 @@ nsBoxFrame::PaintChildren(nsPresContext*      aPresContext,
     nscoord onePixel = aPresContext->IntScaledPixelsToTwips(1);
     GetContentRect(r);
 
-    if (NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+    if (NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
       GetDebugMargin(debugMargin);
       PixelMarginToTwips(aPresContext, debugMargin);
       r.Deflate(debugMargin);
@@ -1684,7 +1684,7 @@ nsBoxFrame::PaintChildren(nsPresContext*      aPresContext,
 
     GetChildBox(&kid);
     while (nsnull != kid) {
-         if (!hasClipped && NS_STYLE_OVERFLOW_HIDDEN == disp->mOverflow) {
+         if (!hasClipped && NS_STYLE_OVERFLOW_CLIP == disp->mOverflow) {
             // if we haven't already clipped and we should
             // check to see if the child is in out bounds. If not then
             // we begin clipping.