From b8499fbfc0216da671febd35fe33b3e65e95484a Mon Sep 17 00:00:00 2001
From: "dbaron%dbaron.org"
 <dbaron%dbaron.org@18797224-902f-48f8-a5cc-f745e15eee43>
Date: Sat, 4 Sep 2004 06:53:36 +0000
Subject: [PATCH] Land bug 72747 in pieces:  Simplify the mechanisms used to
 prevent framesets from having scrollbars and used to implement the scrolling
 attribute on frames and iframes.  Implement scrolling='yes'.  b=72747 
 r+sr=roc

git-svn-id: svn://10.0.0.236/trunk@161744 18797224-902f-48f8-a5cc-f745e15eee43
---
 mozilla/content/base/src/nsDocumentViewer.cpp | 24 ++----
 .../html/document/src/nsHTMLContentSink.cpp   | 20 +----
 .../html/document/src/nsHTMLDocument.h        |  5 ++
 .../html/document/src/nsIHTMLDocument.h       |  3 +
 .../html/document/src/nsMediaDocument.cpp     |  7 --
 .../xml/document/src/nsXMLContentSink.cpp     |  7 --
 mozilla/docshell/base/nsDocShell.cpp          | 72 ++---------------
 mozilla/docshell/base/nsDocShell.h            |  1 -
 mozilla/docshell/base/nsIScrollable.idl       |  5 +-
 .../browser/webBrowser/nsWebBrowser.cpp       | 26 ------
 mozilla/layout/base/nsCSSFrameConstructor.cpp | 32 ++------
 mozilla/layout/base/nsDocumentViewer.cpp      | 24 ++----
 mozilla/layout/generic/nsGfxScrollFrame.cpp   | 79 +++++++++++++------
 .../layout/html/base/src/nsGfxScrollFrame.cpp | 79 +++++++++++++------
 .../html/style/src/nsCSSFrameConstructor.cpp  | 32 ++------
 15 files changed, 154 insertions(+), 262 deletions(-)

diff --git a/mozilla/content/base/src/nsDocumentViewer.cpp b/mozilla/content/base/src/nsDocumentViewer.cpp
index 088a22c32b2..37d82603967 100644
--- a/mozilla/content/base/src/nsDocumentViewer.cpp
+++ b/mozilla/content/base/src/nsDocumentViewer.cpp
@@ -120,7 +120,7 @@
 #include "nsIFocusController.h"
 
 #include "nsIScrollableView.h"
-#include "nsIScrollable.h"
+#include "nsIHTMLDocument.h"
 #include "nsITimelineService.h"
 #include "nsGfxCIID.h"
 
@@ -678,23 +678,11 @@ DocumentViewerImpl::InitPresentationStuff(PRBool aDoInitialReflow)
   mViewManager->SetDefaultBackgroundColor(mPresContext->DefaultBackgroundColor());
 
   if (aDoInitialReflow) {
-    nsCOMPtr<nsIScrollable> sc = do_QueryInterface(mContainer);
-
-    if (sc) {
-      nsCOMPtr<nsIDOMHTMLFrameSetElement> frameset(do_QueryInterface(mDocument->GetRootContent()));
-
-      if (frameset) {
-        // If this is a frameset (i.e. not a frame) then we never want
-        // scrollbars on it, the scrollbars go inside the frames
-        // inside the frameset...
-
-        sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                           nsIScrollable::Scrollbar_Never);
-        sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                           nsIScrollable::Scrollbar_Never);
-      } else {
-        sc->ResetScrollbarPreferences();
-      }
+    nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(mDocument);
+    if (htmlDoc) {
+      nsCOMPtr<nsIDOMHTMLFrameSetElement> frameset =
+        do_QueryInterface(mDocument->GetRootContent());
+      htmlDoc->SetIsFrameset(frameset != nsnull);
     }
 
     // Initial reflow
diff --git a/mozilla/content/html/document/src/nsHTMLContentSink.cpp b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
index 650b90da514..f2f2fefb770 100644
--- a/mozilla/content/html/document/src/nsHTMLContentSink.cpp
+++ b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
@@ -108,7 +108,6 @@
 #include "nsTimer.h"
 #include "nsITimer.h"
 #include "nsDOMError.h"
-#include "nsIScrollable.h"
 #include "nsContentPolicyUtils.h"
 #include "nsIScriptContext.h"
 #include "nsStyleLinkElement.h"
@@ -3646,24 +3645,9 @@ HTMLContentSink::StartLayout()
 
   mLastNotificationTime = PR_Now();
 
-  // If it's a frameset document then disable scrolling.
-  // Else, reset scrolling to default settings for this shell.
-  // This must happen before the initial reflow, when we create the root frame
-  nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(mDocShell);
-  if (scrollableContainer) {
-    if (mFrameset) {
-      scrollableContainer->
-        SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                       nsIScrollable::Scrollbar_Never);
-      scrollableContainer->
-        SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                       nsIScrollable::Scrollbar_Never);
-    } else {
-      scrollableContainer->ResetScrollbarPreferences();
-    }
-  }
+  mHTMLDocument->SetIsFrameset(mFrameset != nsnull);
 
-  nsContentSink::StartLayout(!!mFrameset);
+  nsContentSink::StartLayout(mFrameset != nsnull);
 }
 
 void
diff --git a/mozilla/content/html/document/src/nsHTMLDocument.h b/mozilla/content/html/document/src/nsHTMLDocument.h
index 3ff0e760270..3b0037b6e86 100644
--- a/mozilla/content/html/document/src/nsHTMLDocument.h
+++ b/mozilla/content/html/document/src/nsHTMLDocument.h
@@ -119,6 +119,9 @@ public:
     return mWriteLevel != PRUint32(0);
   }
 
+  virtual PRBool GetIsFrameset() { return mIsFrameset; }
+  virtual void SetIsFrameset(PRBool aFrameset) { mIsFrameset = aFrameset; }
+
   virtual void ContentAppended(nsIContent* aContainer,
                                PRInt32 aNewIndexInContainer);
   virtual void ContentInserted(nsIContent* aContainer,
@@ -319,6 +322,8 @@ protected:
    */
   PRPackedBool mDomainWasSet;
 
+  PRPackedBool mIsFrameset;
+
   PLDHashTable mIdAndNameHashTable;
 
   nsCOMPtr<nsIWyciwygChannel> mWyciwygChannel;
diff --git a/mozilla/content/html/document/src/nsIHTMLDocument.h b/mozilla/content/html/document/src/nsIHTMLDocument.h
index ab9848cfbc8..12eae9914b5 100644
--- a/mozilla/content/html/document/src/nsIHTMLDocument.h
+++ b/mozilla/content/html/document/src/nsIHTMLDocument.h
@@ -111,6 +111,9 @@ public:
   virtual PRInt32 GetNumFormsSynchronous() = 0;
   
   virtual PRBool IsWriting() = 0;
+
+  virtual PRBool GetIsFrameset() = 0;
+  virtual void SetIsFrameset(PRBool aFrameset) = 0;
 };
 
 #endif /* nsIHTMLDocument_h___ */
diff --git a/mozilla/content/html/document/src/nsMediaDocument.cpp b/mozilla/content/html/document/src/nsMediaDocument.cpp
index c23378527df..2fe13f86d56 100644
--- a/mozilla/content/html/document/src/nsMediaDocument.cpp
+++ b/mozilla/content/html/document/src/nsMediaDocument.cpp
@@ -267,13 +267,6 @@ nsMediaDocument::CreateSyntheticDocument()
 nsresult
 nsMediaDocument::StartLayout()
 {
-  // Reset scrolling to default settings for this shell.
-  // This must happen before the initial reflow, when we create the root frame
-  nsCOMPtr<nsIScrollable> scrollableContainer(do_QueryReferent(mDocumentContainer));
-  if (scrollableContainer) {
-    scrollableContainer->ResetScrollbarPreferences();
-  }
-
   PRUint32 numberOfShells = GetNumberOfShells();
   for (PRUint32 i = 0; i < numberOfShells; i++) {
     nsIPresShell *shell = GetShellAt(i);
diff --git a/mozilla/content/xml/document/src/nsXMLContentSink.cpp b/mozilla/content/xml/document/src/nsXMLContentSink.cpp
index 4c8ba67f5aa..5a87993f2ba 100644
--- a/mozilla/content/xml/document/src/nsXMLContentSink.cpp
+++ b/mozilla/content/xml/document/src/nsXMLContentSink.cpp
@@ -78,7 +78,6 @@
 #include "prlog.h"
 #include "prmem.h"
 #include "nsParserUtils.h"
-#include "nsIScrollable.h"
 #include "nsRect.h"
 #include "nsGenericElement.h"
 #include "nsIWebNavigation.h"
@@ -832,12 +831,6 @@ nsXMLContentSink::PopContent()
 void
 nsXMLContentSink::StartLayout()
 {
-  // Reset scrolling to default settings for this shell.
-  // This must happen before the initial reflow, when we create the root frame
-  nsCOMPtr<nsIScrollable> scrollableContainer(do_QueryInterface(mDocShell));
-  if (scrollableContainer) {
-    scrollableContainer->ResetScrollbarPreferences();
-  }
   PRBool topLevelFrameset = PR_FALSE;
   nsCOMPtr<nsIDocShellTreeItem> docShellAsItem(do_QueryInterface(mDocShell));
   if (docShellAsItem) {
diff --git a/mozilla/docshell/base/nsDocShell.cpp b/mozilla/docshell/base/nsDocShell.cpp
index e412428bd2a..486c4fe72b6 100644
--- a/mozilla/docshell/base/nsDocShell.cpp
+++ b/mozilla/docshell/base/nsDocShell.cpp
@@ -268,7 +268,6 @@ nsDocShell::nsDocShell():
     mMarginHeight(0),
     mItemType(typeContent),
     mContentListener(nsnull),
-    mCurrentScrollbarPref(Scrollbar_Auto, Scrollbar_Auto),
     mDefaultScrollbarPref(Scrollbar_Auto, Scrollbar_Auto),
     mEditorData(nsnull),
     mParent(nsnull),
@@ -3653,29 +3652,6 @@ nsDocShell::SetScrollRangeEx(PRInt32 minHorizontalPos,
     return NS_ERROR_FAILURE;
 }
 
-// Get scroll setting for this document only
-//
-// One important client is nsCSSFrameConstructor::ConstructRootFrame()
-NS_IMETHODIMP
-nsDocShell::GetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
-                                           PRInt32 * scrollbarPref)
-{
-    NS_ENSURE_ARG_POINTER(scrollbarPref);
-    switch (scrollOrientation) {
-    case ScrollOrientation_X:
-        *scrollbarPref = mCurrentScrollbarPref.x;
-        return NS_OK;
-
-    case ScrollOrientation_Y:
-        *scrollbarPref = mCurrentScrollbarPref.y;
-        return NS_OK;
-
-    default:
-        NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
-    }
-    return NS_ERROR_FAILURE;
-}
-
 // This returns setting for all documents in this webshell
 NS_IMETHODIMP
 nsDocShell::GetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
@@ -3697,39 +3673,14 @@ nsDocShell::GetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
     return NS_ERROR_FAILURE;
 }
 
-// Set scrolling preference for this document only.
+// Set scrolling preference for all documents in this shell
 //
 // There are three possible values stored in the shell:
-//  1) NS_STYLE_OVERFLOW_HIDDEN = no scrollbars
-//  2) NS_STYLE_OVERFLOW_AUTO = scrollbars appear if needed
-//  3) NS_STYLE_OVERFLOW_SCROLL = scrollbars always
+//  1) nsIScrollable::Scrollbar_Never = no scrollbar
+//  2) nsIScrollable::Scrollbar_Auto = scrollbar appears if the document
+//     being displayed would normally have scrollbar
+//  3) nsIScrollable::Scrollbar_Always = scrollbar always appears
 //
-// XXX Currently OVERFLOW_SCROLL isn't honored,
-//     as it is not implemented by Gfx scrollbars
-// XXX setting has no effect after the root frame is created
-//     as it is not implemented by Gfx scrollbars
-//
-// One important client is HTMLContentSink::StartLayout()
-NS_IMETHODIMP
-nsDocShell::SetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
-                                           PRInt32 scrollbarPref)
-{
-    switch (scrollOrientation) {
-    case ScrollOrientation_X:
-        mCurrentScrollbarPref.x = scrollbarPref;
-        return NS_OK;
-
-    case ScrollOrientation_Y:
-        mCurrentScrollbarPref.y = scrollbarPref;
-        return NS_OK;
-
-    default:
-        NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
-    }
-    return NS_ERROR_FAILURE;
-}
-
-// Set scrolling preference for all documents in this shell
 // One important client is nsHTMLFrameInnerFrame::CreateWebShell()
 NS_IMETHODIMP
 nsDocShell::SetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
@@ -3750,19 +3701,6 @@ nsDocShell::SetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
     return NS_ERROR_FAILURE;
 }
 
-// Reset 'current' scrollbar settings to 'default'.
-// This must be called before every document load or else
-// frameset scrollbar settings (e.g. <IFRAME SCROLLING="no">
-// will not be preserved.
-//
-// One important client is HTMLContentSink::StartLayout()
-NS_IMETHODIMP
-nsDocShell::ResetScrollbarPreferences()
-{
-    mCurrentScrollbarPref = mDefaultScrollbarPref;
-    return NS_OK;
-}
-
 NS_IMETHODIMP
 nsDocShell::GetScrollbarVisibility(PRBool * verticalVisible,
                                    PRBool * horizontalVisible)
diff --git a/mozilla/docshell/base/nsDocShell.h b/mozilla/docshell/base/nsDocShell.h
index 0806e5541c5..103bce59a1d 100644
--- a/mozilla/docshell/base/nsDocShell.h
+++ b/mozilla/docshell/base/nsDocShell.h
@@ -411,7 +411,6 @@ protected:
     nsCOMPtr<nsIGlobalHistory2> mGlobalHistory;
     nsCOMPtr<nsISupports>      mLoadCookie; // the load cookie associated with the window context.
     nsCOMPtr<nsIWebBrowserFind> mFind;
-    nsPoint                    mCurrentScrollbarPref; // this document only
     nsPoint                    mDefaultScrollbarPref; // persistent across doc loads
     // Reference to the SHEntry for this docshell until the page is destroyed.
     // Somebody give me better name
diff --git a/mozilla/docshell/base/nsIScrollable.idl b/mozilla/docshell/base/nsIScrollable.idl
index fb9616e1d5d..909fc5a39e7 100644
--- a/mozilla/docshell/base/nsIScrollable.idl
+++ b/mozilla/docshell/base/nsIScrollable.idl
@@ -48,7 +48,7 @@
  * min and the max. 
  */
 
-[scriptable, uuid(70bd2967-288b-4d0b-880a-de0b7c15a77c)]
+[scriptable, uuid(919e792a-6490-40b8-bba5-f9e9ad5640c8)]
 interface nsIScrollable : nsISupports
 {
 	/*
@@ -114,11 +114,8 @@ interface nsIScrollable : nsISupports
 	default is 'scrolling preference for all documents in this shell'
 	resetScrollbarPreferences resets current to default
 	*/
-	long getCurrentScrollbarPreferences(in long scrollOrientation);
-	void setCurrentScrollbarPreferences(in long scrollOrientation, in long scrollbarPref);
 	long getDefaultScrollbarPreferences(in long scrollOrientation);
 	void setDefaultScrollbarPreferences(in long scrollOrientation, in long scrollbarPref);
-	void resetScrollbarPreferences();
 
 	/*
 	Get information about whether the vertical and horizontal scrollbars are
diff --git a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
index 18474270d13..eec086f10e9 100644
--- a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
+++ b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
@@ -1524,15 +1524,6 @@ NS_IMETHODIMP nsWebBrowser::SetScrollRangeEx(PRInt32 aMinHorizontalPos,
       aMaxHorizontalPos, aMinVerticalPos, aMaxVerticalPos);
 }
 
-NS_IMETHODIMP nsWebBrowser::GetCurrentScrollbarPreferences(PRInt32 aScrollOrientation,
-   PRInt32* aScrollbarPref)
-{
-   NS_ENSURE_STATE(mDocShell);
-
-   return mDocShellAsScrollable->GetCurrentScrollbarPreferences(aScrollOrientation,
-      aScrollbarPref);
-}
-
 NS_IMETHODIMP nsWebBrowser::GetDefaultScrollbarPreferences(PRInt32 aScrollOrientation,
    PRInt32* aScrollbarPref)
 {
@@ -1542,16 +1533,6 @@ NS_IMETHODIMP nsWebBrowser::GetDefaultScrollbarPreferences(PRInt32 aScrollOrient
       aScrollbarPref);
 }
 
-NS_IMETHODIMP nsWebBrowser::SetCurrentScrollbarPreferences(PRInt32 aScrollOrientation,
-   PRInt32 aScrollbarPref)
-{
-   NS_ENSURE_STATE(mDocShell);
-
-   return mDocShellAsScrollable->SetCurrentScrollbarPreferences(aScrollOrientation,
-      aScrollbarPref);
-
-}
-
 NS_IMETHODIMP nsWebBrowser::SetDefaultScrollbarPreferences(PRInt32 aScrollOrientation,
    PRInt32 aScrollbarPref)
 {
@@ -1561,13 +1542,6 @@ NS_IMETHODIMP nsWebBrowser::SetDefaultScrollbarPreferences(PRInt32 aScrollOrient
       aScrollbarPref);
 }
 
-NS_IMETHODIMP nsWebBrowser::ResetScrollbarPreferences()
-{
-   NS_ENSURE_STATE(mDocShell);
-
-   return mDocShellAsScrollable->ResetScrollbarPreferences();
-}
-
 NS_IMETHODIMP nsWebBrowser::GetScrollbarVisibility(PRBool* aVerticalVisible,
    PRBool* aHorizontalVisible)
 {
diff --git a/mozilla/layout/base/nsCSSFrameConstructor.cpp b/mozilla/layout/base/nsCSSFrameConstructor.cpp
index 1d484213ebb..a5c0948f6d3 100644
--- a/mozilla/layout/base/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/base/nsCSSFrameConstructor.cpp
@@ -3824,7 +3824,6 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   // for print-preview, but not when printing), then create a scroll frame that
   // will act as the scrolling mechanism for the viewport. 
   // XXX Do we even need a viewport when printing to a printer?
-  PRBool isScrollable = PR_TRUE;
 
   //isScrollable = PR_FALSE;
 
@@ -3837,8 +3836,6 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   //  2) NS_STYLE_OVERFLOW_AUTO = scrollbars appear if needed
   //  3) NS_STYLE_OVERFLOW_SCROLL = scrollbars always
   // Only need to create a scroll frame/view for cases 2 and 3.
-  // Currently OVERFLOW_SCROLL isn't honored, as
-  // scrollportview::SetScrollPref is not implemented.
 
   PRBool isHTML = aDocElement->IsContentOfType(nsIContent::eHTML);
   PRBool isXUL = PR_FALSE;
@@ -3848,28 +3845,13 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   }
 
   // Never create scrollbars for XUL documents
-#ifdef MOZ_XUL
-  if (isXUL) {
-    isScrollable = PR_FALSE;
-  } else 
-#endif
-  {
-    nsresult rv;
-    if (aPresContext) {
-      nsCOMPtr<nsISupports> container = aPresContext->GetContainer();
-      if (container) {
-        nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(container, &rv);
-        if (NS_SUCCEEDED(rv) && scrollableContainer) {
-          PRInt32 scrolling = -1;
-          // XXX We should get prefs for X and Y and deal with these independently!
-          scrollableContainer->GetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,&scrolling);
-          if (nsIScrollable::Scrollbar_Never == scrolling) {
-            isScrollable = PR_FALSE;
-          }
-          // XXX NS_STYLE_OVERFLOW_SCROLL should create 'always on' scrollbars
-        }
-      }
-    }
+  PRBool isScrollable = !isXUL;
+
+  // Never create scrollbars for frameset documents.
+  if (isHTML) {
+    nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(mDocument);
+    if (htmlDoc && htmlDoc->GetIsFrameset())
+      isScrollable = PR_FALSE;
   }
 
   if (isPaginated) {
diff --git a/mozilla/layout/base/nsDocumentViewer.cpp b/mozilla/layout/base/nsDocumentViewer.cpp
index 088a22c32b2..37d82603967 100644
--- a/mozilla/layout/base/nsDocumentViewer.cpp
+++ b/mozilla/layout/base/nsDocumentViewer.cpp
@@ -120,7 +120,7 @@
 #include "nsIFocusController.h"
 
 #include "nsIScrollableView.h"
-#include "nsIScrollable.h"
+#include "nsIHTMLDocument.h"
 #include "nsITimelineService.h"
 #include "nsGfxCIID.h"
 
@@ -678,23 +678,11 @@ DocumentViewerImpl::InitPresentationStuff(PRBool aDoInitialReflow)
   mViewManager->SetDefaultBackgroundColor(mPresContext->DefaultBackgroundColor());
 
   if (aDoInitialReflow) {
-    nsCOMPtr<nsIScrollable> sc = do_QueryInterface(mContainer);
-
-    if (sc) {
-      nsCOMPtr<nsIDOMHTMLFrameSetElement> frameset(do_QueryInterface(mDocument->GetRootContent()));
-
-      if (frameset) {
-        // If this is a frameset (i.e. not a frame) then we never want
-        // scrollbars on it, the scrollbars go inside the frames
-        // inside the frameset...
-
-        sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                           nsIScrollable::Scrollbar_Never);
-        sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                           nsIScrollable::Scrollbar_Never);
-      } else {
-        sc->ResetScrollbarPreferences();
-      }
+    nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(mDocument);
+    if (htmlDoc) {
+      nsCOMPtr<nsIDOMHTMLFrameSetElement> frameset =
+        do_QueryInterface(mDocument->GetRootContent());
+      htmlDoc->SetIsFrameset(frameset != nsnull);
     }
 
     // Initial reflow
diff --git a/mozilla/layout/generic/nsGfxScrollFrame.cpp b/mozilla/layout/generic/nsGfxScrollFrame.cpp
index 4608c28c76c..00c7d8dc942 100644
--- a/mozilla/layout/generic/nsGfxScrollFrame.cpp
+++ b/mozilla/layout/generic/nsGfxScrollFrame.cpp
@@ -45,6 +45,7 @@
 #include "nsIServiceManager.h"
 #include "nsIView.h"
 #include "nsIScrollableView.h"
+#include "nsIScrollable.h"
 #include "nsIViewManager.h"
 #include "nsHTMLContainerFrame.h"
 #include "nsWidgetsCID.h"
@@ -1181,40 +1182,72 @@ NS_IMETHODIMP_(nsrefcnt) nsGfxScrollFrameInner::Release(void)
 
 NS_IMPL_QUERY_INTERFACE1(nsGfxScrollFrameInner, nsIScrollPositionListener)
 
+static void HandleScrollPref(nsIScrollable *aScrollable, PRInt32 aOrientation,
+                             PRUint8& aValue)
+{
+  PRInt32 pref;
+  aScrollable->GetDefaultScrollbarPreferences(aOrientation, &pref);
+  switch (pref) {
+    case nsIScrollable::Scrollbar_Auto:
+      // leave |aValue| untouched
+      break;
+    case nsIScrollable::Scrollbar_Never:
+      aValue = NS_STYLE_OVERFLOW_HIDDEN;
+      break;
+    case nsIScrollable::Scrollbar_Always:
+      aValue = NS_STYLE_OVERFLOW_SCROLL;
+      break;
+  }
+}
+
+static nsGfxScrollFrameInner::ScrollbarStyles
+ConvertOverflow(PRUint8 aOverflow)
+{
+  nsGfxScrollFrameInner::ScrollbarStyles result;
+  switch (aOverflow) {
+    case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
+      result.mHorizontal = NS_STYLE_OVERFLOW_HIDDEN;
+      result.mVertical = NS_STYLE_OVERFLOW_SCROLL;
+      break;
+    case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
+      result.mHorizontal = NS_STYLE_OVERFLOW_SCROLL;
+      result.mVertical = NS_STYLE_OVERFLOW_HIDDEN;
+      break;
+    default:
+      result.mHorizontal = aOverflow;
+      result.mVertical = aOverflow;
+  }
+  return result;
+}
+
 nsGfxScrollFrameInner::ScrollbarStyles
 nsGfxScrollFrameInner::GetScrollbarStylesFromFrame() const
 {
-  PRUint8 overflow;
+  ScrollbarStyles result;
   nsIFrame* parent = mOuter->GetParent();
   if (parent && parent->GetType() == nsLayoutAtoms::viewportFrame &&
       // Make sure we're actually the root scrollframe
       parent->GetFirstChild(nsnull) ==
         NS_STATIC_CAST(const nsIFrame*, mOuter)) {
-    overflow = mOuter->GetPresContext()->GetViewportOverflowOverride();
+    nsPresContext *presContext = mOuter->GetPresContext();
+    result = ConvertOverflow(presContext->GetViewportOverflowOverride());
+
+    nsCOMPtr<nsISupports> container = presContext->GetContainer();
+    nsCOMPtr<nsIScrollable> scrollable = do_QueryInterface(container);
+    HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_X,
+                     result.mHorizontal);
+    HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_Y,
+                     result.mVertical);
   } else {
-    overflow = mOuter->GetStyleDisplay()->mOverflow;
+    result = ConvertOverflow(mOuter->GetStyleDisplay()->mOverflow);
   }
 
-  switch (overflow) {
-  case NS_STYLE_OVERFLOW_SCROLL:
-  case NS_STYLE_OVERFLOW_HIDDEN:
-  case NS_STYLE_OVERFLOW_VISIBLE: // should never happen
-  case NS_STYLE_OVERFLOW_AUTO:
-    return ScrollbarStyles(overflow, overflow);
-  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);
-  case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
-    return ScrollbarStyles(NS_STYLE_OVERFLOW_SCROLL, NS_STYLE_OVERFLOW_HIDDEN);
-  default:
-    NS_NOTREACHED("invalid overflow value");
-    return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN);
-  }
+  NS_ASSERTION(result.mHorizontal != NS_STYLE_OVERFLOW_VISIBLE &&
+               result.mHorizontal != NS_STYLE_OVERFLOW_CLIP &&
+               result.mVertical != NS_STYLE_OVERFLOW_VISIBLE &&
+               result.mVertical != NS_STYLE_OVERFLOW_CLIP,
+               "scrollbars should not have been created");
+  return result;
 }
 
 void
diff --git a/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp b/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
index 4608c28c76c..00c7d8dc942 100644
--- a/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
+++ b/mozilla/layout/html/base/src/nsGfxScrollFrame.cpp
@@ -45,6 +45,7 @@
 #include "nsIServiceManager.h"
 #include "nsIView.h"
 #include "nsIScrollableView.h"
+#include "nsIScrollable.h"
 #include "nsIViewManager.h"
 #include "nsHTMLContainerFrame.h"
 #include "nsWidgetsCID.h"
@@ -1181,40 +1182,72 @@ NS_IMETHODIMP_(nsrefcnt) nsGfxScrollFrameInner::Release(void)
 
 NS_IMPL_QUERY_INTERFACE1(nsGfxScrollFrameInner, nsIScrollPositionListener)
 
+static void HandleScrollPref(nsIScrollable *aScrollable, PRInt32 aOrientation,
+                             PRUint8& aValue)
+{
+  PRInt32 pref;
+  aScrollable->GetDefaultScrollbarPreferences(aOrientation, &pref);
+  switch (pref) {
+    case nsIScrollable::Scrollbar_Auto:
+      // leave |aValue| untouched
+      break;
+    case nsIScrollable::Scrollbar_Never:
+      aValue = NS_STYLE_OVERFLOW_HIDDEN;
+      break;
+    case nsIScrollable::Scrollbar_Always:
+      aValue = NS_STYLE_OVERFLOW_SCROLL;
+      break;
+  }
+}
+
+static nsGfxScrollFrameInner::ScrollbarStyles
+ConvertOverflow(PRUint8 aOverflow)
+{
+  nsGfxScrollFrameInner::ScrollbarStyles result;
+  switch (aOverflow) {
+    case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
+      result.mHorizontal = NS_STYLE_OVERFLOW_HIDDEN;
+      result.mVertical = NS_STYLE_OVERFLOW_SCROLL;
+      break;
+    case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
+      result.mHorizontal = NS_STYLE_OVERFLOW_SCROLL;
+      result.mVertical = NS_STYLE_OVERFLOW_HIDDEN;
+      break;
+    default:
+      result.mHorizontal = aOverflow;
+      result.mVertical = aOverflow;
+  }
+  return result;
+}
+
 nsGfxScrollFrameInner::ScrollbarStyles
 nsGfxScrollFrameInner::GetScrollbarStylesFromFrame() const
 {
-  PRUint8 overflow;
+  ScrollbarStyles result;
   nsIFrame* parent = mOuter->GetParent();
   if (parent && parent->GetType() == nsLayoutAtoms::viewportFrame &&
       // Make sure we're actually the root scrollframe
       parent->GetFirstChild(nsnull) ==
         NS_STATIC_CAST(const nsIFrame*, mOuter)) {
-    overflow = mOuter->GetPresContext()->GetViewportOverflowOverride();
+    nsPresContext *presContext = mOuter->GetPresContext();
+    result = ConvertOverflow(presContext->GetViewportOverflowOverride());
+
+    nsCOMPtr<nsISupports> container = presContext->GetContainer();
+    nsCOMPtr<nsIScrollable> scrollable = do_QueryInterface(container);
+    HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_X,
+                     result.mHorizontal);
+    HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_Y,
+                     result.mVertical);
   } else {
-    overflow = mOuter->GetStyleDisplay()->mOverflow;
+    result = ConvertOverflow(mOuter->GetStyleDisplay()->mOverflow);
   }
 
-  switch (overflow) {
-  case NS_STYLE_OVERFLOW_SCROLL:
-  case NS_STYLE_OVERFLOW_HIDDEN:
-  case NS_STYLE_OVERFLOW_VISIBLE: // should never happen
-  case NS_STYLE_OVERFLOW_AUTO:
-    return ScrollbarStyles(overflow, overflow);
-  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);
-  case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
-    return ScrollbarStyles(NS_STYLE_OVERFLOW_SCROLL, NS_STYLE_OVERFLOW_HIDDEN);
-  default:
-    NS_NOTREACHED("invalid overflow value");
-    return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN);
-  }
+  NS_ASSERTION(result.mHorizontal != NS_STYLE_OVERFLOW_VISIBLE &&
+               result.mHorizontal != NS_STYLE_OVERFLOW_CLIP &&
+               result.mVertical != NS_STYLE_OVERFLOW_VISIBLE &&
+               result.mVertical != NS_STYLE_OVERFLOW_CLIP,
+               "scrollbars should not have been created");
+  return result;
 }
 
 void
diff --git a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
index 1d484213ebb..a5c0948f6d3 100644
--- a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
@@ -3824,7 +3824,6 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   // for print-preview, but not when printing), then create a scroll frame that
   // will act as the scrolling mechanism for the viewport. 
   // XXX Do we even need a viewport when printing to a printer?
-  PRBool isScrollable = PR_TRUE;
 
   //isScrollable = PR_FALSE;
 
@@ -3837,8 +3836,6 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   //  2) NS_STYLE_OVERFLOW_AUTO = scrollbars appear if needed
   //  3) NS_STYLE_OVERFLOW_SCROLL = scrollbars always
   // Only need to create a scroll frame/view for cases 2 and 3.
-  // Currently OVERFLOW_SCROLL isn't honored, as
-  // scrollportview::SetScrollPref is not implemented.
 
   PRBool isHTML = aDocElement->IsContentOfType(nsIContent::eHTML);
   PRBool isXUL = PR_FALSE;
@@ -3848,28 +3845,13 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
   }
 
   // Never create scrollbars for XUL documents
-#ifdef MOZ_XUL
-  if (isXUL) {
-    isScrollable = PR_FALSE;
-  } else 
-#endif
-  {
-    nsresult rv;
-    if (aPresContext) {
-      nsCOMPtr<nsISupports> container = aPresContext->GetContainer();
-      if (container) {
-        nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(container, &rv);
-        if (NS_SUCCEEDED(rv) && scrollableContainer) {
-          PRInt32 scrolling = -1;
-          // XXX We should get prefs for X and Y and deal with these independently!
-          scrollableContainer->GetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,&scrolling);
-          if (nsIScrollable::Scrollbar_Never == scrolling) {
-            isScrollable = PR_FALSE;
-          }
-          // XXX NS_STYLE_OVERFLOW_SCROLL should create 'always on' scrollbars
-        }
-      }
-    }
+  PRBool isScrollable = !isXUL;
+
+  // Never create scrollbars for frameset documents.
+  if (isHTML) {
+    nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(mDocument);
+    if (htmlDoc && htmlDoc->GetIsFrameset())
+      isScrollable = PR_FALSE;
   }
 
   if (isPaginated) {