Bug 840480 r=roc

layout/base/RestyleTracker.cpp

@@ -109,8 +109,7 @@ CollectRestyles(nsISupports* aElement,
 inline void
 RestyleTracker::ProcessOneRestyle(Element* aElement,
                                   nsRestyleHint aRestyleHint,
-                                  nsChangeHint aChangeHint,
+                                  nsChangeHint aChangeHint)
-                                  OverflowChangedTracker& aTracker)
 {
   NS_PRECONDITION((aRestyleHint & eRestyle_LaterSiblings) == 0,
                   "Someone should have handled this before calling us");
@@ -122,15 +121,14 @@ RestyleTracker::ProcessOneRestyle(Element* aElement,
   if (aRestyleHint & (eRestyle_Self | eRestyle_Subtree)) {
     mFrameConstructor->RestyleElement(aElement, primaryFrame, aChangeHint,
                                       *this,
-                                      (aRestyleHint & eRestyle_Subtree) != 0, 
+                                      (aRestyleHint & eRestyle_Subtree) != 0);
-                                      aTracker);
   } else if (aChangeHint &&
              (primaryFrame ||
               (aChangeHint & nsChangeHint_ReconstructFrame))) {
     // Don't need to recompute style; just apply the hint
     nsStyleChangeList changeList;
     changeList.AppendChange(primaryFrame, aElement, aChangeHint);
-    mFrameConstructor->ProcessRestyledFrames(changeList, aTracker);
+    mFrameConstructor->ProcessRestyledFrames(changeList);
   }
 }
 
@@ -144,8 +142,6 @@ RestyleTracker::DoProcessRestyles()
 
   mFrameConstructor->mInStyleRefresh = true;
 
-  OverflowChangedTracker tracker;
-
   // loop so that we process any restyle events generated by processing
   while (mPendingRestyles.Count()) {
     if (mHaveLaterSiblingRestyles) {
@@ -210,7 +206,7 @@ RestyleTracker::DoProcessRestyles()
         continue;
       }
 
-      ProcessOneRestyle(element, data.mRestyleHint, data.mChangeHint, tracker);
+      ProcessOneRestyle(element, data.mRestyleHint, data.mChangeHint);
     }
 
     if (mHaveLaterSiblingRestyles) {
@@ -239,13 +235,12 @@ RestyleTracker::DoProcessRestyles()
            ++currentRestyle) {
         ProcessOneRestyle(currentRestyle->mElement,
                           currentRestyle->mRestyleHint,
-                          currentRestyle->mChangeHint,
+                          currentRestyle->mChangeHint);
-                          tracker);
       }
     }
   }
 
-  tracker.Flush();
+  mFrameConstructor->FlushOverflowChangedTracker();
 
   // Set mInStyleRefresh to false now, since the EndUpdate call might
   // add more restyles.

layout/base/RestyleTracker.h

@@ -31,6 +31,11 @@ class OverflowChangedTracker
 {
 public:
 
+  ~OverflowChangedTracker()
+  {
+    NS_ASSERTION(mEntryList.empty(), "Need to flush before destroying!");
+  }
+
   /**
    * Add a frame that has had a style change, and needs its
    * overflow updated.
@@ -247,8 +252,7 @@ private:
    */
   inline void ProcessOneRestyle(Element* aElement,
                                 nsRestyleHint aRestyleHint,
-                                nsChangeHint aChangeHint,
+                                nsChangeHint aChangeHint);
-                                OverflowChangedTracker& aTracker);
 
   /**
    * The guts of our restyle processing.

layout/base/nsCSSFrameConstructor.cpp

@@ -1437,7 +1437,6 @@ nsCSSFrameConstructor::nsCSSFrameConstructor(nsIDocument *aDocument,
   , mInStyleRefresh(false)
   , mHoverGeneration(0)
   , mRebuildAllExtraHint(nsChangeHint(0))
-  , mOverflowChangedTracker(nullptr)
   , mAnimationGeneration(0)
   , mPendingRestyles(ELEMENT_HAS_PENDING_RESTYLE |
                      ELEMENT_IS_POTENTIAL_RESTYLE_ROOT, this)
@@ -1517,9 +1516,7 @@ nsCSSFrameConstructor::NotifyDestroyingFrame(nsIFrame* aFrame)
     CountersDirty();
   }
 
-  if (mOverflowChangedTracker) {
+  mOverflowChangedTracker.RemoveFrame(aFrame);
-    mOverflowChangedTracker->RemoveFrame(aFrame);
-  }
 
   nsFrameManager::NotifyDestroyingFrame(aFrame);
 }
@@ -8201,8 +8198,7 @@ NeedToReframeForAddingOrRemovingTransform(nsIFrame* aFrame)
 }
 
 nsresult
-nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
+nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
-                                             OverflowChangedTracker& aTracker)
 {
   NS_ASSERTION(!nsContentUtils::IsSafeToRunScript(),
                "Someone forgot a script blocker");
@@ -8212,10 +8208,6 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
 
   SAMPLE_LABEL("CSS", "ProcessRestyledFrames");
 
-  MOZ_ASSERT(!GetOverflowChangedTracker(), 
-             "Can't have multiple overflow changed trackers!");
-  SetOverflowChangedTracker(&aTracker);
-
   // Make sure to not rebuild quote or counter lists while we're
   // processing restyles
   BeginUpdate();
@@ -8346,7 +8338,7 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
             // updating overflows since that will happen when it's reflowed.
             if (!(childFrame->GetStateBits() &
                   (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) {
-              aTracker.AddFrame(childFrame);
+              mOverflowChangedTracker.AddFrame(childFrame);
             }
             NS_ASSERTION(!nsLayoutUtils::GetNextContinuationOrSpecialSibling(childFrame),
                          "SVG frames should not have continuations or special siblings");
@@ -8359,7 +8351,7 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
         if (!(frame->GetStateBits() &
               (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) {
           while (frame) {
-            aTracker.AddFrame(frame);
+            mOverflowChangedTracker.AddFrame(frame);
 
             frame =
               nsLayoutUtils::GetNextContinuationOrSpecialSibling(frame);
@@ -8401,7 +8393,6 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList,
 #endif
   }
 
-  SetOverflowChangedTracker(nullptr);
   aChangeList.Clear();
   return NS_OK;
 }
@@ -8411,8 +8402,7 @@ nsCSSFrameConstructor::RestyleElement(Element        *aElement,
                                       nsIFrame       *aPrimaryFrame,
                                       nsChangeHint   aMinHint,
                                       RestyleTracker& aRestyleTracker,
-                                      bool            aRestyleDescendants,
+                                      bool            aRestyleDescendants)
-                                      OverflowChangedTracker& aTracker)
 {
   NS_ASSERTION(aPrimaryFrame == aElement->GetPrimaryFrame(),
                "frame/content mismatch");
@@ -8450,7 +8440,7 @@ nsCSSFrameConstructor::RestyleElement(Element        *aElement,
     nsStyleChangeList changeList;
     ComputeStyleChangeFor(aPrimaryFrame, &changeList, aMinHint,
                           aRestyleTracker, aRestyleDescendants);
-    ProcessRestyledFrames(changeList, aTracker);
+    ProcessRestyledFrames(changeList);
   } else {
     // no frames, reconstruct for content
     MaybeRecreateFramesForElement(aElement);
@@ -12234,9 +12224,8 @@ nsCSSFrameConstructor::DoRebuildAllStyleData(RestyleTracker& aRestyleTracker,
                         &changeList, aExtraHint,
                         aRestyleTracker, true);
   // Process the required changes
-  OverflowChangedTracker tracker;
+  ProcessRestyledFrames(changeList);
-  ProcessRestyledFrames(changeList, tracker);
+  FlushOverflowChangedTracker();
-  tracker.Flush();
 
   // Tell the style set it's safe to destroy the old rule tree.  We
   // must do this after the ProcessRestyledFrames call in case the

layout/base/nsCSSFrameConstructor.h

@@ -241,8 +241,7 @@ public:
   // This function does not call ProcessAttachedQueue() on the binding manager.
   // If the caller wants that to happen synchronously, it needs to handle that
   // itself.
-  nsresult ProcessRestyledFrames(nsStyleChangeList& aRestyleArray,
+  nsresult ProcessRestyledFrames(nsStyleChangeList& aRestyleArray);
-                                 OverflowChangedTracker& aTracker);
 
 private:
 
@@ -307,13 +306,9 @@ public:
     PostRestyleEventCommon(aElement, aRestyleHint, aMinChangeHint, true);
   }
 
-  OverflowChangedTracker *GetOverflowChangedTracker() const 
+  void FlushOverflowChangedTracker() 
-  { 
-    return mOverflowChangedTracker; 
-  }
-  void SetOverflowChangedTracker(OverflowChangedTracker *aTracker)
   {
-    mOverflowChangedTracker = aTracker;    
+    mOverflowChangedTracker.Flush();
   }
 
 private:
@@ -406,8 +401,7 @@ private:
                       nsIFrame*       aPrimaryFrame,
                       nsChangeHint    aMinHint,
                       RestyleTracker& aRestyleTracker,
-                      bool            aRestyleDescendants,
+                      bool            aRestyleDescendants);
-                      OverflowChangedTracker& aTracker);
 
   nsresult InitAndRestoreFrame (const nsFrameConstructorState& aState,
                                 nsIContent*                    aContent,
@@ -1914,7 +1908,7 @@ private:
 
   nsCOMPtr<nsILayoutHistoryState> mTempFrameTreeState;
 
-  OverflowChangedTracker *mOverflowChangedTracker;
+  OverflowChangedTracker mOverflowChangedTracker;
 
   // The total number of animation flushes by this frame constructor.
   // Used to keep the layer and animation manager in sync.

layout/base/nsPresShell.cpp

@@ -2734,9 +2734,8 @@ PresShell::RecreateFramesFor(nsIContent* aContent)
 
   // Mark ourselves as not safe to flush while we're doing frame construction.
   ++mChangeNestCount;
-  css::OverflowChangedTracker tracker;
+  nsresult rv = mFrameConstructor->ProcessRestyledFrames(changeList);
-  nsresult rv = mFrameConstructor->ProcessRestyledFrames(changeList, tracker);
+  mFrameConstructor->FlushOverflowChangedTracker();
-  tracker.Flush();
   --mChangeNestCount;
   
   return rv;
@@ -7899,9 +7898,8 @@ PresShell::Observe(nsISupports* aSubject,
         {
           nsAutoScriptBlocker scriptBlocker;
           ++mChangeNestCount;
-          css::OverflowChangedTracker tracker;
+          mFrameConstructor->ProcessRestyledFrames(changeList);
-          mFrameConstructor->ProcessRestyledFrames(changeList, tracker);
+          mFrameConstructor->FlushOverflowChangedTracker();
-          tracker.Flush();
           --mChangeNestCount;
         }
       }

layout/style/nsTransitionManager.cpp

@@ -429,10 +429,10 @@ nsTransitionManager::UpdateAllThrottledStyles()
     }
   }
 
-  OverflowChangedTracker tracker;
   mPresContext->PresShell()->FrameConstructor()->
-    ProcessRestyledFrames(changeList, tracker);
+    ProcessRestyledFrames(changeList);
-  tracker.Flush();
+  mPresContext->PresShell()->FrameConstructor()->
+    FlushOverflowChangedTracker();
 }
 
 already_AddRefed<nsIStyleRule>