Bug 1125422 - Fold touch and scroll listener flags into a single apz-aware flag for better code reuse. r=roc

layout/base/nsDisplayList.cpp

@@ -587,8 +587,7 @@ nsDisplayListBuilder::nsDisplayListBuilder(nsIFrame* aReferenceFrame,
       mIsPaintingToWindow(false),
       mIsCompositingCheap(false),
       mContainsPluginItem(false),
-      mAncestorHasTouchEventHandler(false),
-      mAncestorHasScrollEventHandler(false),
+      mAncestorHasApzAwareEventHandler(false),
       mHaveScrollableDisplayPort(false),
       mWindowDraggingAllowed(false),
       mIsBuildingForPopup(nsLayoutUtils::IsPopup(aReferenceFrame))
@@ -3151,9 +3150,7 @@ nsDisplayLayerEventRegions::AddFrame(nsDisplayListBuilder* aBuilder,
   } else {
     mHitRegion.Or(mHitRegion, borderBox);
   }
-  if (aBuilder->GetAncestorHasTouchEventHandler() ||
-      aBuilder->GetAncestorHasScrollEventHandler())
-  {
+  if (aBuilder->GetAncestorHasApzAwareEventHandler()) {
     mDispatchToContentHitRegion.Or(mDispatchToContentHitRegion, borderBox);
   }
 }

layout/base/nsDisplayList.h

@@ -345,15 +345,10 @@ public:
     return CurrentPresShellState()->mInsidePointerEventsNoneDoc;
   }
 
-  bool GetAncestorHasTouchEventHandler() { return mAncestorHasTouchEventHandler; }
-  void SetAncestorHasTouchEventHandler(bool aValue)
+  bool GetAncestorHasApzAwareEventHandler() { return mAncestorHasApzAwareEventHandler; }
+  void SetAncestorHasApzAwareEventHandler(bool aValue)
   {
-    mAncestorHasTouchEventHandler = aValue;
-  }
-  bool GetAncestorHasScrollEventHandler() { return mAncestorHasScrollEventHandler; }
-  void SetAncestorHasScrollEventHandler(bool aValue)
-  {
-    mAncestorHasScrollEventHandler = aValue;
+    mAncestorHasApzAwareEventHandler = aValue;
   }
 
   bool HaveScrollableDisplayPort() const { return mHaveScrollableDisplayPort; }
@@ -578,8 +573,7 @@ public:
         mPrevOffset(aBuilder->mCurrentOffsetToReferenceFrame),
         mPrevDirtyRect(aBuilder->mDirtyRect),
         mPrevIsAtRootOfPseudoStackingContext(aBuilder->mIsAtRootOfPseudoStackingContext),
-        mPrevAncestorHasTouchEventHandler(aBuilder->mAncestorHasTouchEventHandler),
-        mPrevAncestorHasScrollEventHandler(aBuilder->mAncestorHasScrollEventHandler)
+        mPrevAncestorHasApzAwareEventHandler(aBuilder->mAncestorHasApzAwareEventHandler)
     {
       if (aForChild->IsTransformed()) {
         aBuilder->mCurrentOffsetToReferenceFrame = nsPoint();
@@ -624,8 +618,7 @@ public:
       mBuilder->mCurrentOffsetToReferenceFrame = mPrevOffset;
       mBuilder->mDirtyRect = mPrevDirtyRect;
       mBuilder->mIsAtRootOfPseudoStackingContext = mPrevIsAtRootOfPseudoStackingContext;
-      mBuilder->mAncestorHasTouchEventHandler = mPrevAncestorHasTouchEventHandler;
-      mBuilder->mAncestorHasScrollEventHandler = mPrevAncestorHasScrollEventHandler;
+      mBuilder->mAncestorHasApzAwareEventHandler = mPrevAncestorHasApzAwareEventHandler;
       mBuilder->mCurrentAnimatedGeometryRoot = mPrevAnimatedGeometryRoot;
     }
   private:
@@ -637,8 +630,7 @@ public:
     nsPoint               mPrevOffset;
     nsRect                mPrevDirtyRect;
     bool                  mPrevIsAtRootOfPseudoStackingContext;
-    bool                  mPrevAncestorHasTouchEventHandler;
-    bool                  mPrevAncestorHasScrollEventHandler;
+    bool                  mPrevAncestorHasApzAwareEventHandler;
   };
 
   /**
@@ -920,8 +912,7 @@ private:
   bool                           mIsPaintingToWindow;
   bool                           mIsCompositingCheap;
   bool                           mContainsPluginItem;
-  bool                           mAncestorHasTouchEventHandler;
-  bool                           mAncestorHasScrollEventHandler;
+  bool                           mAncestorHasApzAwareEventHandler;
   // True when the first async-scrollable scroll frame for which we build a
   // display list has a display port. An async-scrollable scroll frame is one
   // which WantsAsyncScroll().

layout/base/nsLayoutUtils.cpp

@@ -7838,3 +7838,16 @@ nsLayoutUtils::SetBSizeFromFontMetrics(const nsIFrame* aFrame,
                                aFramePadding.BStart(aFrameWM));
   aMetrics.BSize(aLineWM) += aFramePadding.BStartEnd(aFrameWM);
 }
+
+/* static */ bool
+nsLayoutUtils::HasApzAwareListeners(EventListenerManager* aElm)
+{
+  if (!aElm) {
+    return false;
+  }
+  return aElm->HasListenersFor(nsGkAtoms::ontouchstart) ||
+         aElm->HasListenersFor(nsGkAtoms::ontouchmove) ||
+         aElm->HasListenersFor(nsGkAtoms::onwheel) ||
+         aElm->HasListenersFor(nsGkAtoms::onDOMMouseScroll) ||
+         aElm->HasListenersFor(nsHtml5Atoms::onmousewheel);
+}

layout/base/nsLayoutUtils.h

@@ -63,6 +63,7 @@ struct nsStyleImageOrientation;
 struct nsOverflowAreas;
 
 namespace mozilla {
+class EventListenerManager;
 class SVGImageContext;
 struct IntrinsicSize;
 struct ContainerLayerParameters;
@@ -2551,6 +2552,8 @@ public:
                                       mozilla::WritingMode aLineWM,
                                       mozilla::WritingMode aFrameWM);
 
+  static bool HasApzAwareListeners(mozilla::EventListenerManager* aElm);
+
 private:
   static uint32_t sFontSizeInflationEmPerLine;
   static uint32_t sFontSizeInflationMinTwips;

layout/generic/nsFrame.cpp

@@ -1909,18 +1909,8 @@ CheckForApzAwareEventHandlers(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame)
     return;
   }
   EventListenerManager* elm = nsContentUtils::GetExistingListenerManagerForNode(content);
-  if (!elm) {
-    return;
-  }
-  if (elm->HasListenersFor(nsGkAtoms::ontouchstart) ||
-      elm->HasListenersFor(nsGkAtoms::ontouchmove)) {
-    aBuilder->SetAncestorHasTouchEventHandler(true);
-  }
-  if (elm->HasListenersFor(nsGkAtoms::onwheel) ||
-      elm->HasListenersFor(nsGkAtoms::onDOMMouseScroll) ||
-      elm->HasListenersFor(nsHtml5Atoms::onmousewheel))
-  {
-    aBuilder->SetAncestorHasScrollEventHandler(true);
+  if (nsLayoutUtils::HasApzAwareListeners(elm)) {
+    aBuilder->SetAncestorHasApzAwareEventHandler(true);
   }
 }
 

layout/generic/nsSubDocumentFrame.cpp

@@ -487,8 +487,7 @@ nsSubDocumentFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
               ? nsLayoutUtils::FindOrCreateIDFor(rootScrollFrame->GetContent())
               : aBuilder->GetCurrentScrollParentId());
 
-      aBuilder->SetAncestorHasTouchEventHandler(false);
-      aBuilder->SetAncestorHasScrollEventHandler(false);
+      aBuilder->SetAncestorHasApzAwareEventHandler(false);
       subdocRootFrame->
         BuildDisplayListForStackingContext(aBuilder, dirty, &childItems);
     }