Bug 1368547 - Remove nsFrameManagerBase::mPlaceholderMap and instead store the placeholder on a frame property on the out-of-flow

Tag #1375

layout/generic/ReflowInput.cpp

@@ -1564,8 +1564,7 @@ ReflowInput::InitAbsoluteConstraints(nsPresContext* aPresContext,
   // have been if it had been in the flow
   nsHypotheticalPosition hypotheticalPos;
   if ((iStartIsAuto && iEndIsAuto) || (bStartIsAuto && bEndIsAuto)) {
-    nsIFrame* placeholderFrame =
-      aPresContext->PresShell()->GetPlaceholderFrameFor(mFrame);
+    nsPlaceholderFrame* placeholderFrame = mFrame->GetPlaceholderFrame();
     NS_ASSERTION(placeholderFrame, "no placeholder frame");
 
     if (placeholderFrame->HasAnyStateBits(

layout/generic/nsAbsoluteContainingBlock.cpp

@@ -338,17 +338,9 @@ nsAbsoluteContainingBlock::DoMarkFramesDirty(bool aMarkAllDirty)
 // Given an out-of-flow frame, this method returns the parent frame of
 // its placeholder frame, if that parent is a nsContainerFrame.
 static nsContainerFrame*
-GetPlaceholderContainer(nsPresContext* aPresContext,
-                        nsIFrame* aPositionedFrame)
+GetPlaceholderContainer(nsIFrame* aPositionedFrame)
 {
-  MOZ_ASSERT(aPositionedFrame, "need non-null frame");
-  MOZ_ASSERT(aPositionedFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW),
-             "expecting abspos frame");
-  MOZ_ASSERT(aPresContext && aPresContext == aPositionedFrame->PresContext(),
-             "need non-null pres context which matches our frame");
-
-  nsIFrame* placeholder =
-    aPresContext->PresShell()->GetPlaceholderFrameFor(aPositionedFrame);
+  nsIFrame* placeholder = aPositionedFrame->GetPlaceholderFrame();
 
   if (!placeholder) {
     return nullptr;
@@ -557,8 +549,7 @@ nsAbsoluteContainingBlock::ResolveSizeDependentOffsets(
         aOffsets->IEnd(outerWM) - aMargin.IStartEnd(outerWM) -
         aKidSize.ISize(outerWM);
     } else if (aKidReflowInput.mFlags.mIOffsetsNeedCSSAlign) {
-      placeholderContainer = GetPlaceholderContainer(aPresContext,
-                                                     aKidReflowInput.mFrame);
+      placeholderContainer = GetPlaceholderContainer(aKidReflowInput.mFrame);
       nscoord offset = OffsetToAlignedStaticPos(aKidReflowInput, aKidSize,
                                                 logicalCBSizeOuterWM,
                                                 placeholderContainer,
@@ -579,8 +570,7 @@ nsAbsoluteContainingBlock::ResolveSizeDependentOffsets(
         aKidSize.BSize(outerWM);
     } else if (aKidReflowInput.mFlags.mBOffsetsNeedCSSAlign) {
       if (!placeholderContainer) {
-        placeholderContainer = GetPlaceholderContainer(aPresContext,
-                                                       aKidReflowInput.mFrame);
+        placeholderContainer = GetPlaceholderContainer(aKidReflowInput.mFrame);
       }
       nscoord offset = OffsetToAlignedStaticPos(aKidReflowInput, aKidSize,
                                                 logicalCBSizeOuterWM,
@@ -655,8 +645,7 @@ nsAbsoluteContainingBlock::ReflowAbsoluteFrame(nsIFrame*                aDelegat
     // due to the multiple coordinate spaces in play, we use a convenience flag
     // to simply have the child's ReflowInput give it a static position at its
     // abs.pos. CB origin, and then we'll align & offset it from there.
-    nsIFrame* placeholder =
-      aPresContext->PresShell()->GetPlaceholderFrameFor(aKidFrame);
+    nsIFrame* placeholder = aKidFrame->GetPlaceholderFrame();
     if (placeholder && placeholder->GetParent() == aDelegatingFrame) {
       rsFlags |= ReflowInput::STATIC_POS_IS_CB_ORIGIN;
     }

layout/generic/nsBlockFrame.cpp

@@ -4336,8 +4336,7 @@ CheckPlaceholderInLine(nsIFrame* aBlock, nsLineBox* aLine, nsFloatCache* aFC)
                "float in a line should never be a continuation");
   NS_ASSERTION(!(aFC->mFloat->GetStateBits() & NS_FRAME_IS_PUSHED_FLOAT),
                "float in a line should never be a pushed float");
-  nsIFrame* ph = aBlock->PresContext()->FrameManager()->
-                   GetPlaceholderFrameFor(aFC->mFloat->FirstInFlow());
+  nsIFrame* ph = aFC->mFloat->FirstInFlow()->GetPlaceholderFrame();
   for (nsIFrame* f = ph; f; f = f->GetParent()) {
     if (f->GetParent() == aBlock)
       return aLine->Contains(f);
@@ -4939,9 +4938,8 @@ nsBlockFrame::DrainSelfPushedFloats()
       if (f->GetPrevContinuation()) {
         // FIXME
       } else {
-        nsPlaceholderFrame *placeholder =
-          presContext->FrameManager()->GetPlaceholderFrameFor(f);
-        nsIFrame *floatOriginalParent = presContext->PresShell()->
+        nsPlaceholderFrame* placeholder = f->GetPlaceholderFrame();
+        nsIFrame* floatOriginalParent = presContext->PresShell()->
           FrameConstructor()->GetFloatContainingBlock(placeholder);
         if (floatOriginalParent != this) {
           // This is a first continuation that was pushed from one of our
@@ -5565,7 +5563,7 @@ FindChildContaining(nsBlockFrame* aFrame, nsIFrame* aFindFrame)
       return nullptr;
     if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW))
       break;
-    aFindFrame = aFrame->PresContext()->FrameManager()->GetPlaceholderFrameFor(child);
+    aFindFrame = child->GetPlaceholderFrame();
   }
 
   return child;
@@ -6847,9 +6845,8 @@ nsBlockFrame::ChildIsDirty(nsIFrame* aChild)
       AddStateBits(NS_BLOCK_LOOK_FOR_DIRTY_FRAMES);
     } else {
       NS_ASSERTION(aChild->IsFloating(), "should be a float");
-      nsIFrame *thisFC = FirstContinuation();
-      nsIFrame *placeholderPath =
-        PresContext()->FrameManager()->GetPlaceholderFrameFor(aChild);
+      nsIFrame* thisFC = FirstContinuation();
+      nsIFrame* placeholderPath = aChild->GetPlaceholderFrame();
       // SVG code sometimes sends FrameNeedsReflow notifications during
       // frame destruction, leading to null placeholders, but we're safe
       // ignoring those.

layout/generic/nsFirstLetterFrame.cpp

@@ -320,8 +320,7 @@ nsFirstLetterFrame::CreateContinuationForFloatingParent(nsPresContext* aPresCont
   *aContinuation = nullptr;
 
   nsIPresShell* presShell = aPresContext->PresShell();
-  nsPlaceholderFrame* placeholderFrame =
-    presShell->FrameManager()->GetPlaceholderFrameFor(this);
+  nsPlaceholderFrame* placeholderFrame = GetPlaceholderFrame();
   nsContainerFrame* parent = placeholderFrame->GetParent();
 
   nsIFrame* continuation = presShell->FrameConstructor()->

layout/generic/nsFrame.cpp

@@ -633,8 +633,7 @@ nsFrame::DestroyFrom(nsIFrame* aDestructRoot)
 
   nsIPresShell *shell = presContext->GetPresShell();
   if (mState & NS_FRAME_OUT_OF_FLOW) {
-    nsPlaceholderFrame* placeholder =
-      shell->FrameManager()->GetPlaceholderFrameFor(this);
+    nsPlaceholderFrame* placeholder = GetPlaceholderFrame();
     NS_ASSERTION(!placeholder || (aDestructRoot != this),
                  "Don't call Destroy() on OOFs, call Destroy() on the placeholder.");
     NS_ASSERTION(!placeholder ||
@@ -642,7 +641,6 @@ nsFrame::DestroyFrom(nsIFrame* aDestructRoot)
                  "Placeholder relationship should have been torn down already; "
                  "this might mean we have a stray placeholder in the tree.");
     if (placeholder) {
-      shell->FrameManager()->UnregisterPlaceholderFrame(placeholder);
       placeholder->SetOutOfFlowFrame(nullptr);
     }
   }
@@ -8060,9 +8058,8 @@ int32_t
 nsFrame::GetLineNumber(nsIFrame *aFrame, bool aLockScroll, nsIFrame** aContainingBlock)
 {
   NS_ASSERTION(aFrame, "null aFrame");
-  nsFrameManager* frameManager = aFrame->PresContext()->FrameManager();
-  nsIFrame *blockFrame = aFrame;
-  nsIFrame *thisBlock;
+  nsIFrame* blockFrame = aFrame;
+  nsIFrame* thisBlock;
   nsAutoLineIterator it;
   nsresult result = NS_ERROR_FAILURE;
   while (NS_FAILED(result) && blockFrame)
@@ -8075,7 +8072,7 @@ nsFrame::GetLineNumber(nsIFrame *aFrame, bool aLockScroll, nsIFrame** aContainin
         // abspos continuations don't have placeholders, get the fif
         thisBlock = thisBlock->FirstInFlow();
       }
-      thisBlock = frameManager->GetPlaceholderFrameFor(thisBlock);
+      thisBlock = thisBlock->GetPlaceholderFrame();
       if (!thisBlock)
         return -1;
     }  
@@ -9027,7 +9024,6 @@ nsStyleContext*
 nsFrame::DoGetParentStyleContext(nsIFrame** aProviderFrame) const
 {
   *aProviderFrame = nullptr;
-  nsFrameManager* fm = PresContext()->FrameManager();
 
   // Handle display:contents and the root frame, when there's no parent frame
   // to inherit from.
@@ -9044,6 +9040,7 @@ nsFrame::DoGetParentStyleContext(nsIFrame** aProviderFrame) const
           /* if next is true then it's really a request for the table frame's
              parent context, see nsTable[Outer]Frame::GetParentStyleContext. */
           pseudo == nsCSSAnonBoxes::tableWrapper) {
+        nsFrameManager* fm = PresContext()->FrameManager();
         nsStyleContext* sc = fm->GetDisplayContentsStyleFor(parentContent);
         if (MOZ_UNLIKELY(sc)) {
           return sc;
@@ -9080,7 +9077,7 @@ nsFrame::DoGetParentStyleContext(nsIFrame** aProviderFrame) const
   // We're an out-of-flow frame.  For out-of-flow frames, we must
   // resolve underneath the placeholder's parent.  The placeholder is
   // reached from the first-in-flow.
-  nsIFrame* placeholder = fm->GetPlaceholderFrameFor(FirstInFlow());
+  nsIFrame* placeholder = FirstInFlow()->GetPlaceholderFrame();
   if (!placeholder) {
     NS_NOTREACHED("no placeholder frame for out-of-flow frame");
     *aProviderFrame = GetCorrectedParent(this);

layout/generic/nsIFrame.h

@@ -82,6 +82,7 @@ class nsLineList_iterator;
 class nsAbsoluteContainingBlock;
 class nsIContent;
 class nsContainerFrame;
+class nsPlaceholderFrame;
 
 struct nsPeekOffsetStruct;
 struct nsPoint;
@@ -728,6 +729,16 @@ public:
    */
   inline nsContainerFrame* GetInFlowParent();
 
+  /**
+   * Return the placeholder for this frame (which must be out-of-flow).
+   * @note this will only return non-null if |this| is the first-in-flow
+   * although we don't assert that here for legacy reasons.
+   */
+  inline nsPlaceholderFrame* GetPlaceholderFrame() const {
+    MOZ_ASSERT(HasAnyStateBits(NS_FRAME_OUT_OF_FLOW));
+    return GetProperty(PlaceholderFrameProperty());
+  }
+
   /**
    * Set this frame's parent to aParent.
    * If the frame may have moved into or out of a scrollframe's
@@ -1047,6 +1058,8 @@ public:
 
   NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BidiDataProperty, mozilla::FrameBidiData)
 
+  NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(PlaceholderFrameProperty, nsPlaceholderFrame)
+
   mozilla::FrameBidiData GetBidiData()
   {
     return GetProperty(BidiDataProperty());

layout/generic/nsIFrameInlines.h

@@ -166,8 +166,8 @@ nsContainerFrame*
 nsIFrame::GetInFlowParent()
 {
   if (GetStateBits() & NS_FRAME_OUT_OF_FLOW) {
-    nsFrameManager* fm = PresContext()->FrameManager();
-    return fm->GetPlaceholderFrameFor(FirstContinuation())->GetParent();
+    nsIFrame* ph = FirstContinuation()->GetProperty(nsIFrame::PlaceholderFrameProperty());
+    return ph->GetParent();
   }
 
   return GetParent();

layout/generic/nsPlaceholderFrame.cpp

@@ -156,16 +156,15 @@ nsPlaceholderFrame::DestroyFrom(nsIFrame* aDestructRoot)
 {
   nsIFrame* oof = mOutOfFlowFrame;
   if (oof) {
-    // Unregister out-of-flow frame
-    nsFrameManager* fm = PresContext()->GetPresShell()->FrameManager();
-    fm->UnregisterPlaceholderFrame(this);
     mOutOfFlowFrame = nullptr;
+    oof->DeleteProperty(nsIFrame::PlaceholderFrameProperty());
     // If aDestructRoot is not an ancestor of the out-of-flow frame,
     // then call RemoveFrame on it here.
     // Also destroy it here if it's a popup frame. (Bug 96291)
     if ((GetStateBits() & PLACEHOLDER_FOR_POPUP) ||
         !nsLayoutUtils::IsProperAncestorFrame(aDestructRoot, oof)) {
       ChildListID listId = nsLayoutUtils::GetChildListNameFor(oof);
+      nsFrameManager* fm = PresContext()->GetPresShell()->FrameManager();
       fm->RemoveFrame(listId, oof);
     }
     // else oof will be destroyed by its parent

layout/generic/nsTextFrame.cpp

@@ -1383,8 +1383,7 @@ BuildTextRuns(DrawTarget* aDrawTarget, nsTextFrame* aForFrame,
   nsIFrame* lineContainerChild = aForFrame;
   if (!aLineContainer) {
     if (aForFrame->IsFloatingFirstLetterChild()) {
-      lineContainerChild = aForFrame->PresContext()->PresShell()->
-        GetPlaceholderFrameFor(aForFrame->GetParent());
+      lineContainerChild = aForFrame->GetParent()->GetPlaceholderFrame();
     }
     aLineContainer = FindLineContainer(lineContainerChild);
   } else {