Bug 10209 - Part 6: Implement the CSS "containing block" concept correctly as a binary relation, as opposed to a unary relation; r=bzbarsky

layout/base/nsLayoutUtils.cpp

@@ -2108,10 +2108,7 @@ GetPercentHeight(const nsStyleCoord& aStyle,
   if (eStyleUnit_Percent != aStyle.GetUnit())
     return PR_FALSE;
 
-  nsIFrame *f;
-  for (f = aFrame->GetParent(); f && !f->IsContainingBlock();
-       f = f->GetParent())
-    ;
+  nsIFrame *f = aFrame->GetContainingBlock();
   if (!f) {
     NS_NOTREACHED("top of frame tree not a containing block");
     return PR_FALSE;

layout/base/nsLayoutUtils.h

@@ -780,6 +780,13 @@ public:
    */
   static nsBlockFrame* GetAsBlock(nsIFrame* aFrame);
 
+  /*
+   * Whether the frame is an nsBlockFrame which is not a wrapper block.
+   */
+  static bool IsNonWrapperBlock(nsIFrame* aFrame) {
+    return GetAsBlock(aFrame) && !aFrame->IsBlockWrapper();
+  }
+
   /**
    * If aFrame is an out of flow frame, return its placeholder, otherwise
    * return its parent.

layout/forms/nsFieldSetFrame.cpp

@@ -106,7 +106,6 @@ public:
                          nsIFrame*      aOldFrame);
 
   virtual nsIAtom* GetType() const;
-  virtual bool IsContainingBlock() const;
 
 #ifdef ACCESSIBILITY  
   virtual already_AddRefed<nsAccessible> CreateAccessible();
@@ -151,12 +150,6 @@ nsFieldSetFrame::GetType() const
   return nsGkAtoms::fieldSetFrame;
 }
 
-bool
-nsFieldSetFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 NS_IMETHODIMP
 nsFieldSetFrame::SetInitialChildList(ChildListID    aListID,
                                      nsFrameList&   aChildList)

layout/forms/nsHTMLButtonControlFrame.cpp

@@ -361,12 +361,6 @@ nsHTMLButtonControlFrame::ReflowButtonContents(nsPresContext* aPresContext,
   aDesiredSize.ascent += yoff;
 }
 
-/* virtual */ bool
-nsHTMLButtonControlFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 PRIntn
 nsHTMLButtonControlFrame::GetSkipSides() const
 {

layout/forms/nsHTMLButtonControlFrame.h

@@ -79,8 +79,6 @@ public:
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus);
 
-  virtual bool IsContainingBlock() const;
-  
   NS_IMETHOD HandleEvent(nsPresContext* aPresContext, 
                          nsGUIEvent* aEvent,
                          nsEventStatus* aEventStatus);

layout/forms/nsListControlFrame.cpp

@@ -1758,15 +1758,6 @@ nsListControlFrame::GetType() const
   return nsGkAtoms::listControlFrame; 
 }
 
-bool
-nsListControlFrame::IsContainingBlock() const
-{
-  // We are in fact the containing block for our options.  They should
-  // certainly not use our parent block (or worse yet our parent combobox) for
-  // their sizing.
-  return PR_TRUE;
-}
-
 void
 nsListControlFrame::InvalidateInternal(const nsRect& aDamageRect,
                                        nscoord aX, nscoord aY, nsIFrame* aForChild,

layout/forms/nsListControlFrame.h

@@ -124,8 +124,6 @@ public:
       ~(nsIFrame::eReplaced | nsIFrame::eReplacedContainsBlock));
   }
 
-  virtual bool IsContainingBlock() const;
-
   virtual void InvalidateInternal(const nsRect& aDamageRect,
                                   nscoord aX, nscoord aY, nsIFrame* aForChild,
                                   PRUint32 aFlags);

layout/generic/nsBlockFrame.cpp

@@ -629,22 +629,6 @@ nsBlockFrame::GetChildLists(nsTArray<ChildList>* aLists) const
   }
 }
 
-/* virtual */ bool
-nsBlockFrame::IsContainingBlock() const
-{
-  // The block wrappers we use to wrap blocks inside inlines aren't
-  // described in the CSS spec.  We need to make them not be containing
-  // blocks for the cases where we care about the 'direction' property
-  // of an element's containing block.
-  // Since the parent of such a block is either a normal block or
-  // another such pseudo, this shouldn't cause anything bad to happen.
-  // Also the anonymous blocks inside table cells are not containing blocks.
-  nsIAtom *pseudoType = GetStyleContext()->GetPseudo();
-  return pseudoType != nsCSSAnonBoxes::mozAnonymousBlock &&
-         pseudoType != nsCSSAnonBoxes::mozAnonymousPositionedBlock &&
-         pseudoType != nsCSSAnonBoxes::cellContent;
-}
-
 /* virtual */ bool
 nsBlockFrame::IsFloatContainingBlock() const
 {

layout/generic/nsBlockFrame.h

@@ -181,7 +181,6 @@ public:
   virtual nscoord GetCaretBaseline() const;
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
   virtual nsSplittableType GetSplittableType() const;
-  virtual bool IsContainingBlock() const;
   virtual bool IsFloatContainingBlock() const;
   NS_IMETHOD BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                               const nsRect&           aDirtyRect,

layout/generic/nsCanvasFrame.h

@@ -88,7 +88,6 @@ public:
                     nsHTMLReflowMetrics&     aDesiredSize,
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus);
-  virtual bool IsContainingBlock() const { return true; }
   virtual bool IsFrameOfType(PRUint32 aFlags) const
   {
     return nsHTMLContainerFrame::IsFrameOfType(aFlags &

layout/generic/nsFrame.cpp

@@ -1787,7 +1787,6 @@ nsIFrame::BuildDisplayListForChild(nsDisplayListBuilder*   aBuilder,
   // XXX we REALLY need a "are you an inline-block sort of thing?" here!!!
   if ((aFlags & DISPLAY_CHILD_INLINE) &&
       (disp->mDisplay != NS_STYLE_DISPLAY_INLINE ||
-       aChild->IsContainingBlock() ||
        (aChild->IsFrameOfType(eReplaced)))) {
     // child is a non-inline frame in an inline context, i.e.,
     // it acts like inline-block or inline-table. Therefore it is a
@@ -4905,16 +4904,43 @@ nsFrame::IsFrameTreeTooDeep(const nsHTMLReflowState& aReflowState,
   return PR_FALSE;
 }
 
-/* virtual */ bool nsFrame::IsContainingBlock() const
+bool
+nsIFrame::IsBlockWrapper() const
 {
-  const nsStyleDisplay* display = GetStyleDisplay();
+  nsIAtom *pseudoType = GetStyleContext()->GetPseudo();
+  return (pseudoType == nsCSSAnonBoxes::mozAnonymousBlock ||
+          pseudoType == nsCSSAnonBoxes::mozAnonymousPositionedBlock ||
+          pseudoType == nsCSSAnonBoxes::cellContent);
+}
 
-  // Absolute positioning causes |display->mDisplay| to be set to block,
-  // if needed.
-  return display->mDisplay == NS_STYLE_DISPLAY_BLOCK || 
-         display->mDisplay == NS_STYLE_DISPLAY_INLINE_BLOCK || 
-         display->mDisplay == NS_STYLE_DISPLAY_LIST_ITEM ||
-         display->mDisplay == NS_STYLE_DISPLAY_TABLE_CELL;
+static nsIFrame*
+GetNearestBlockContainer(nsIFrame* frame)
+{
+  // The block wrappers we use to wrap blocks inside inlines aren't
+  // described in the CSS spec.  We need to make them not be containing
+  // blocks.
+  // Since the parent of such a block is either a normal block or
+  // another such pseudo, this shouldn't cause anything bad to happen.
+  // Also the anonymous blocks inside table cells are not containing blocks.
+  while (frame->IsFrameOfType(nsIFrame::eLineParticipant) ||
+         frame->IsBlockWrapper()) {
+    frame = frame->GetParent();
+    NS_ASSERTION(frame, "How come we got to the root frame without seeing a containing block?");
+  }
+  return frame;
+}
+
+nsIFrame*
+nsIFrame::GetContainingBlock() const
+{
+  // MathML frames might have absolute positioning style, but they would
+  // still be in-flow.  So we have to check to make sure that the frame
+  // is really out-of-flow too.
+  if (GetStyleDisplay()->IsAbsolutelyPositioned() &&
+      (GetStateBits() & NS_FRAME_OUT_OF_FLOW)) {
+    return GetParent(); // the parent is always the containing block
+  }
+  return GetNearestBlockContainer(GetParent());
 }
 
 #ifdef NS_DEBUG

layout/generic/nsFrame.h

@@ -231,7 +231,6 @@ public:
   NS_IMETHOD  SetNextInFlow(nsIFrame*);
   NS_IMETHOD  GetOffsetFromView(nsPoint& aOffset, nsIView** aView) const;
   virtual nsIAtom* GetType() const;
-  virtual bool IsContainingBlock() const;
 
   NS_IMETHOD  GetSelected(bool *aSelected) const;
   NS_IMETHOD  IsSelectable(bool* aIsSelectable, PRUint8* aSelectStyle) const;

layout/generic/nsHTMLReflowState.cpp

@@ -299,31 +299,17 @@ void nsHTMLReflowState::InitCBReflowState()
     return;
   }
 
-  // If outer tables ever become containing blocks, we need to make sure to use
-  // their mCBReflowState in the non-absolutely-positioned case for inner
-  // tables.
-  NS_ASSERTION(frame->GetType() != nsGkAtoms::tableFrame ||
-               !frame->GetParent()->IsContainingBlock(),
-               "Outer table should not be containing block");
-
-  if (parentReflowState->frame->IsContainingBlock() ||
-      // Absolutely positioned frames should always be kids of the frames that
-      // determine their containing block....
-      (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE)) {
-    // an absolutely positioned inner table needs to use the parent of
-    // the outer table.  So the above comment about absolutely
-    // positioned frames is sort of a lie.
-    if (parentReflowState->parentReflowState &&
-        frame->GetType() == nsGkAtoms::tableFrame) {
-      mCBReflowState = parentReflowState->parentReflowState;
+  if (parentReflowState->frame == frame->GetContainingBlock()) {
+    // Inner table frames need to use the containing block of the outer
+    // table frame.
+    if (frame->GetType() == nsGkAtoms::tableFrame) {
+      mCBReflowState = parentReflowState->mCBReflowState;
     } else {
       mCBReflowState = parentReflowState;
     }
-      
-    return;
+  } else {
+    mCBReflowState = parentReflowState->mCBReflowState;
   }
-  
-  mCBReflowState = parentReflowState->mCBReflowState;
 }
 
 /* Check whether CalcQuirkContainingBlockHeight would stop on the
@@ -373,7 +359,7 @@ nsHTMLReflowState::InitResizeFlags(nsPresContext* aPresContext)
     // mCBReflowState->mFlags.mVResize is set correctly below when
     // reflowing descendant.
     mFlags.mVResize = PR_TRUE;
-  } else if (mCBReflowState && !frame->IsContainingBlock()) {
+  } else if (mCBReflowState && !nsLayoutUtils::IsNonWrapperBlock(frame)) {
     // XXX Is this problematic for relatively positioned inlines acting
     // as containing block for absolutely positioned elements?
     // Possibly; in that case we should at least be checking
@@ -415,7 +401,7 @@ nsHTMLReflowState::InitResizeFlags(nsPresContext* aPresContext)
     // line-height depends on block height
     frame->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
     // but only on containing blocks if this frame is not a suitable block
-    dependsOnCBHeight |= !frame->IsContainingBlock();
+    dependsOnCBHeight |= !nsLayoutUtils::IsNonWrapperBlock(frame);
   }
 
   // If we're the descendant of a table cell that performs special height
@@ -488,23 +474,6 @@ nsHTMLReflowState::GetContainingBlockContentWidth(const nsHTMLReflowState* aRefl
   return rs->mComputedWidth;
 }
 
-/* static */
-nsIFrame*
-nsHTMLReflowState::GetContainingBlockFor(const nsIFrame* aFrame)
-{
-  NS_PRECONDITION(aFrame, "Must have frame to work with");
-  nsIFrame* container = aFrame->GetParent();
-  if (aFrame->GetStyleDisplay()->IsAbsolutelyPositioned()) {
-    // Absolutely positioned frames are just kids of their containing
-    // blocks (which may happen to be inlines).
-    return container;
-  }
-  while (container && !container->IsContainingBlock()) {
-    container = container->GetParent();
-  }
-  return container;
-}
-
 void
 nsHTMLReflowState::InitFrameType()
 {
@@ -701,22 +670,12 @@ nsHTMLReflowState::ComputeRelativeOffsets(const nsHTMLReflowState* cbrs,
   }
 }
 
-static nsIFrame*
-GetNearestContainingBlock(nsIFrame *aFrame)
-{
-  nsIFrame *cb = aFrame;
-  do {
-    cb = cb->GetParent();
-  } while (!cb->IsContainingBlock());
-  return cb;
-}
-
 nsIFrame*
 nsHTMLReflowState::GetHypotheticalBoxContainer(nsIFrame* aFrame,
                                                nscoord& aCBLeftEdge,
                                                nscoord& aCBWidth)
 {
-  aFrame = GetNearestContainingBlock(aFrame);
+  aFrame = aFrame->GetContainingBlock();
   NS_ASSERTION(aFrame != frame, "How did that happen?");
 
   /* Now aFrame is the containing block we want */
@@ -1190,7 +1149,7 @@ nsHTMLReflowState::InitAbsoluteConstraints(nsPresContext* aPresContext,
   if (leftIsAuto && rightIsAuto) {
     // Use the direction of the original ("static-position") containing block
     // to dictate whether 'left' or 'right' is treated like 'static-position'.
-    if (NS_STYLE_DIRECTION_LTR == GetNearestContainingBlock(placeholderFrame)
+    if (NS_STYLE_DIRECTION_LTR == placeholderFrame->GetContainingBlock()
                                     ->GetStyleVisibility()->mDirection) {
       NS_ASSERTION(hypotheticalBox.mLeftIsExact, "should always have "
                    "exact value on containing block's start side");
@@ -1570,8 +1529,13 @@ nsHTMLReflowState::ComputeContainingBlockRectangle(nsPresContext*          aPres
   // formed by the content edge of the nearest block-level ancestor
   aContainingBlockWidth = aContainingBlockRS->mComputedWidth;
   aContainingBlockHeight = aContainingBlockRS->mComputedHeight;
-  
-  if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE) {
+
+  // mFrameType for abs-pos tables is NS_CSS_FRAME_TYPE_BLOCK, so we need to
+  // special case them here.
+  if (NS_FRAME_GET_TYPE(mFrameType) == NS_CSS_FRAME_TYPE_ABSOLUTE ||
+      (frame->GetType() == nsGkAtoms::tableFrame &&
+       frame->GetStyleDisplay()->IsAbsolutelyPositioned() &&
+       (frame->GetParent()->GetStateBits() & NS_FRAME_OUT_OF_FLOW))) {
     // See if the ancestor is block-level or inline-level
     if (NS_FRAME_GET_TYPE(aContainingBlockRS->mFrameType) == NS_CSS_FRAME_TYPE_INLINE) {
       // Base our size on the actual size of the frame.  In cases when this is
@@ -2168,7 +2132,7 @@ nscoord
 nsHTMLReflowState::CalcLineHeight() const
 {
   nscoord blockHeight =
-    frame->IsContainingBlock() ? mComputedHeight :
+    nsLayoutUtils::IsNonWrapperBlock(frame) ? mComputedHeight :
     (mCBReflowState ? mCBReflowState->mComputedHeight : NS_AUTOHEIGHT);
 
   return CalcLineHeight(frame->GetStyleContext(), blockHeight);

layout/generic/nsHTMLReflowState.h

@@ -405,13 +405,6 @@ public:
   static nscoord
     GetContainingBlockContentWidth(const nsHTMLReflowState* aReflowState);
 
-  /**
-   * Find the containing block of aFrame.  This may return null if
-   * there isn't one (but that should really only happen for root
-   * frames).
-   */
-  static nsIFrame* GetContainingBlockFor(const nsIFrame* aFrame);
-
   /**
    * Calculate the used line-height property. The return value will be >= 0.
    */

layout/generic/nsIFrame.h

@@ -1982,9 +1982,17 @@ public:
   }
 
   /**
-   * Is this frame a containing block for non-positioned elements?
+   * Returns true if the frame is a block wrapper.
    */
-  virtual bool IsContainingBlock() const = 0;
+  bool IsBlockWrapper() const;
+
+  /**
+   * Get this frame's CSS containing block.
+   *
+   * The algorithm is defined in
+   * http://www.w3.org/TR/CSS2/visudet.html#containing-block-details.
+   */
+  nsIFrame* GetContainingBlock() const;
 
   /**
    * Is this frame a containing block for floating elements?

layout/generic/nsPageContentFrame.cpp

@@ -168,9 +168,3 @@ nsPageContentFrame::GetFrameName(nsAString& aResult) const
   return MakeFrameName(NS_LITERAL_STRING("PageContent"), aResult);
 }
 #endif
-
-/* virtual */ bool
-nsPageContentFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}

layout/generic/nsPageContentFrame.h

@@ -56,7 +56,6 @@ public:
                      const nsHTMLReflowState& aMaxSize,
                      nsReflowStatus&      aStatus);
 
-  virtual bool IsContainingBlock() const;
   virtual bool IsFrameOfType(PRUint32 aFlags) const
   {
     return ViewportFrame::IsFrameOfType(aFlags &

layout/generic/nsPageFrame.cpp

@@ -175,12 +175,6 @@ nsPageFrame::GetFrameName(nsAString& aResult) const
 }
 #endif
 
-/* virtual */ bool
-nsPageFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 void 
 nsPageFrame::ProcessSpecialCodes(const nsString& aStr, nsString& aNewStr)
 {

layout/generic/nsPageFrame.h

@@ -59,8 +59,6 @@ public:
                               const nsRect&           aDirtyRect,
                               const nsDisplayListSet& aLists);
 
-  virtual bool IsContainingBlock() const;
-
   /**
    * Get the "type" of the frame
    *

layout/generic/nsViewportFrame.cpp

@@ -290,12 +290,6 @@ ViewportFrame::GetType() const
   return nsGkAtoms::viewportFrame;
 }
 
-/* virtual */ bool
-ViewportFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 void
 ViewportFrame::InvalidateInternal(const nsRect& aDamageRect,
                                   nscoord aX, nscoord aY, nsIFrame* aForChild,

layout/generic/nsViewportFrame.h

@@ -100,8 +100,6 @@ public:
    * @see nsGkAtoms::viewportFrame
    */
   virtual nsIAtom* GetType() const;
-  
-  virtual bool IsContainingBlock() const;
 
   virtual void InvalidateInternal(const nsRect& aDamageRect,
                                   nscoord aX, nscoord aY, nsIFrame* aForChild,

layout/reftests/bugs/10209-1.html

@@ -0,0 +1,16 @@
+<!DOCTYPE HTML>
+<style>
+@font-face {
+  font-family: Ahem;
+  src: url(../fonts/Ahem.ttf);
+}
+* {
+  font-family: Ahem;
+}
+</style>
+<body style="font-size: 100px; padding-top: 5px">
+  <div style="position: relative; display: inline;">
+    <table style="height: 50%; position: absolute; width: 50px; background: green">
+    </table>
+  </div>
+</body>

layout/reftests/bugs/10209-2.html

@@ -0,0 +1,16 @@
+<!DOCTYPE HTML>
+<style>
+@font-face {
+  font-family: Ahem;
+  src: url(../fonts/Ahem.ttf);
+}
+* {
+  font-family: Ahem;
+}
+</style>
+<body style="font-size: 100px">
+  <div style="position: relative; height:100px;">
+    <table style="height: 50%; position: absolute; width: 50px; background: green">
+    </table>
+  </div>
+</body>

layout/reftests/bugs/10209-3-ref.html

@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<style>
+@font-face {
+  font-family: Ahem;
+  src: url(../fonts/Ahem.ttf);
+}
+* {
+  font-family: Ahem;
+}
+</style>
+<body style="margin: 0">
+  <div style="width: 100px; height: 100px; background: green">
+  </div>
+</body>

layout/reftests/bugs/10209-3.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<style>
+@font-face {
+  font-family: Ahem;
+  src: url(../fonts/Ahem.ttf);
+}
+* {
+  font-family: Ahem;
+}
+</style>
+<body style="position: relative; display: inline; border-right: 1px solid black; font-size: 100px; line-height: 100px; margin: 0">
+  <table style="position: absolute; width: 100px; height: 100%; top: 0; left: 0; background: green"></table>
+</body>

layout/reftests/bugs/10209-ref.html

@@ -0,0 +1,14 @@
+<!DOCTYPE HTML>
+<style>
+@font-face {
+  font-family: Ahem;
+  src: url(../fonts/Ahem.ttf);
+}
+* {
+  font-family: Ahem;
+}
+</style>
+<body>
+  <div style="width: 50px; height: 50px; background: green">
+  </div>
+</body>

layout/reftests/bugs/reftest.list

@@ -18,6 +18,9 @@
 == 9458-zorder-4.html 9458-zorder-ref-inline-block.html
 == 9458-zorder-5.html 9458-zorder-ref-inline-block.html
 == 10036-1.html 10036-1-ref.html
+skip-if(!cocoaWidget) HTTP(..) == 10209-1.html 10209-ref.html # Bug 667079
+HTTP(..) == 10209-2.html 10209-ref.html
+asserts(4) skip-if(!cocoaWidget) HTTP(..) == 10209-3.html 10209-3-ref.html # Assertions: bug 666606, skip because of bug 667079
 == 18217-basic-1.html 18217-basic-1-ref.html
 == 18217-basic-2a.html 18217-basic-2-ref.html
 == 18217-basic-2b.html 18217-basic-2-ref.html

layout/style/nsComputedDOMStyle.cpp

@@ -131,7 +131,7 @@ GetContainingBlockFor(nsIFrame* aFrame) {
   if (!aFrame) {
     return nsnull;
   }
-  return nsHTMLReflowState::GetContainingBlockFor(aFrame);
+  return aFrame->GetContainingBlock();
 }
 
 nsComputedDOMStyle::nsComputedDOMStyle()
@@ -3332,7 +3332,7 @@ nsComputedDOMStyle::GetLineHeightCoord(nscoord& aCoord)
     if (!mInnerFrame)
       return PR_FALSE;
 
-    if (mInnerFrame->IsContainingBlock()) {
+    if (nsLayoutUtils::IsNonWrapperBlock(mInnerFrame)) {
       blockHeight = mInnerFrame->GetContentRect().height;
     } else {
       GetCBContentHeight(blockHeight);

layout/tables/nsTableCellFrame.cpp

@@ -1043,12 +1043,6 @@ nsTableCellFrame::GetType() const
   return nsGkAtoms::tableCellFrame;
 }
 
-/* virtual */ bool
-nsTableCellFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 #ifdef DEBUG
 NS_IMETHODIMP
 nsTableCellFrame::GetFrameName(nsAString& aResult) const

layout/tables/nsTableCellFrame.h

@@ -149,8 +149,6 @@ public:
    */
   virtual nsIAtom* GetType() const;
 
-  virtual bool IsContainingBlock() const;
-
 #ifdef DEBUG
   NS_IMETHOD GetFrameName(nsAString& aResult) const;
 #endif

layout/tables/nsTableColGroupFrame.cpp

@@ -429,12 +429,6 @@ NS_METHOD nsTableColGroupFrame::Reflow(nsPresContext*          aPresContext,
   return rv;
 }
 
-/* virtual */ bool
-nsTableColGroupFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 nsTableColFrame * nsTableColGroupFrame::GetFirstColumn()
 {
   return GetNextColumn(nsnull);

layout/tables/nsTableColGroupFrame.h

@@ -142,10 +142,6 @@ public:
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus);
 
-  /* needed only because we use Reflow in a hacky way, see
-     nsTableFrame::ReflowColGroups */
-  virtual bool IsContainingBlock() const;
-
   /**
    * Get the "type" of the frame
    *

layout/tables/nsTableFrame.cpp

@@ -359,12 +359,6 @@ nsTableFrame::SetInitialChildList(ChildListID     aListID,
   return NS_OK;
 }
 
-/* virtual */ bool
-nsTableFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 void nsTableFrame::AttributeChangedFor(nsIFrame*       aFrame,
                                        nsIContent*     aContent,
                                        nsIAtom*        aAttribute)

layout/tables/nsTableFrame.h

@@ -164,8 +164,6 @@ public:
   // height reflow will occur. 
   static void RequestSpecialHeightReflow(const nsHTMLReflowState& aReflowState);
 
-  virtual bool IsContainingBlock() const;
-
   static void RePositionViews(nsIFrame* aFrame);
 
   static bool PageBreakAfter(nsIFrame* aSourceFrame,

layout/tables/nsTableOuterFrame.cpp

@@ -199,12 +199,6 @@ nsTableOuterFrame::CreateAccessible()
 }
 #endif
 
-/* virtual */ bool
-nsTableOuterFrame::IsContainingBlock() const
-{
-  return PR_FALSE;
-}
-
 void
 nsTableOuterFrame::DestroyFrom(nsIFrame* aDestructRoot)
 {

layout/tables/nsTableOuterFrame.h

@@ -98,8 +98,6 @@ public:
   // nsIFrame overrides - see there for a description
 
   virtual void DestroyFrom(nsIFrame* aDestructRoot);
-  
-  virtual bool IsContainingBlock() const;
 
   NS_IMETHOD SetInitialChildList(ChildListID     aListID,
                                  nsFrameList&    aChildList);

layout/tables/nsTableRowGroupFrame.cpp

@@ -69,12 +69,6 @@ NS_QUERYFRAME_HEAD(nsTableRowGroupFrame)
   NS_QUERYFRAME_ENTRY(nsTableRowGroupFrame)
 NS_QUERYFRAME_TAIL_INHERITING(nsHTMLContainerFrame)
 
-/* virtual */ bool
-nsTableRowGroupFrame::IsContainingBlock() const
-{
-  return PR_TRUE;
-}
-
 PRInt32
 nsTableRowGroupFrame::GetRowCount()
 {

layout/tables/nsTableRowGroupFrame.h

@@ -149,8 +149,6 @@ public:
    */
   virtual nsIAtom* GetType() const;
 
-  virtual bool IsContainingBlock() const;
-
   nsTableRowFrame* GetFirstRow();
 
 #ifdef DEBUG

layout/xul/base/src/nsScrollbarFrame.cpp

@@ -102,14 +102,6 @@ nsScrollbarFrame::Reflow(nsPresContext*          aPresContext,
   return NS_OK;
 }
 
-/* virtual */ bool
-nsScrollbarFrame::IsContainingBlock() const
-{
-  // Return true so that the nsHTMLReflowState code is happy with us
-  // being a reflow root.
-  return PR_TRUE;
-}
-
 nsIAtom*
 nsScrollbarFrame::GetType() const
 {

layout/xul/base/src/nsScrollbarFrame.h

@@ -96,8 +96,6 @@ public:
                     const nsHTMLReflowState& aReflowState,
                     nsReflowStatus&          aStatus);
 
-  virtual bool IsContainingBlock() const;
-
   virtual nsIAtom* GetType() const;  
 
   void SetScrollbarMediatorContent(nsIContent* aMediator);