Bug 1051985 - Move the scroll handoff parent id from ContainerLayer to Layer. r=mattwoodrow

gfx/layers/Layers.cpp

@@ -172,6 +172,7 @@ Layer::Layer(LayerManager* aManager, void* aImplData) :
   mPrevSibling(nullptr),
   mImplData(aImplData),
   mMaskLayer(nullptr),
+  mScrollHandoffParentId(FrameMetrics::NULL_SCROLL_ID),
   mPostXScale(1.0f),
   mPostYScale(1.0f),
   mOpacity(1.0),
@@ -758,7 +759,6 @@ ContainerLayer::ContainerLayer(LayerManager* aManager, void* aImplData)
   : Layer(aManager, aImplData),
     mFirstChild(nullptr),
     mLastChild(nullptr),
-    mScrollHandoffParentId(FrameMetrics::NULL_SCROLL_ID),
     mPreXScale(1.0f),
     mPreYScale(1.0f),
     mInheritedXScale(1.0f),
@@ -920,8 +920,7 @@ ContainerLayer::RepositionChild(Layer* aChild, Layer* aAfter)
 void
 ContainerLayer::FillSpecificAttributes(SpecificLayerAttributes& aAttrs)
 {
-  aAttrs = ContainerLayerAttributes(mScrollHandoffParentId,
-                                    mPreXScale, mPreYScale,
+  aAttrs = ContainerLayerAttributes(mPreXScale, mPreYScale,
                                     mInheritedXScale, mInheritedYScale,
                                     mBackgroundColor, mContentDescription);
 }
@@ -1443,6 +1442,9 @@ Layer::PrintInfo(std::stringstream& aStream, const char* aPrefix)
   if (!mFrameMetrics.IsDefault()) {
     AppendToString(aStream, mFrameMetrics, " [metrics=", "]");
   }
+  if (mScrollHandoffParentId != FrameMetrics::NULL_SCROLL_ID) {
+    aStream << nsPrintfCString(" [scrollParent=%llu]", mScrollHandoffParentId).get();
+  }
 }
 
 // The static helper function sets the transform matrix into the packet
@@ -1570,9 +1572,6 @@ void
 ContainerLayer::PrintInfo(std::stringstream& aStream, const char* aPrefix)
 {
   Layer::PrintInfo(aStream, aPrefix);
-  if (mScrollHandoffParentId != FrameMetrics::NULL_SCROLL_ID) {
-    aStream << nsPrintfCString(" [scrollParent=%llu]", mScrollHandoffParentId).get();
-  }
   if (UseIntermediateSurface()) {
     aStream << " [usesTmpSurf]";
   }

gfx/layers/Layers.h

@@ -828,6 +828,22 @@ public:
     }
   }
 
+  /**
+   * CONSTRUCTION PHASE ONLY
+   * Set the ViewID of the ContainerLayer to which overscroll should be handed
+   * off. A value of NULL_SCROLL_ID means that the default handoff-parent-finding
+   * behaviour should be used (i.e. walk up the layer tree to find the next
+   * scrollable ancestor layer).
+   */
+  void SetScrollHandoffParentId(FrameMetrics::ViewID aScrollParentId)
+  {
+    if (mScrollHandoffParentId != aScrollParentId) {
+      MOZ_LAYERS_LOG_IF_SHADOWABLE(this, ("Layer::Mutated(%p) ScrollHandoffParentId", this));
+      mScrollHandoffParentId = aScrollParentId;
+      Mutated();
+    }
+  }
+
   /*
    * Compositor event handling
    * =========================
@@ -1135,6 +1151,7 @@ public:
   uint32_t GetContentFlags() { return mContentFlags; }
   const nsIntRegion& GetVisibleRegion() { return mVisibleRegion; }
   const FrameMetrics& GetFrameMetrics() const { return mFrameMetrics; }
+  FrameMetrics::ViewID GetScrollHandoffParentId() const { return mScrollHandoffParentId; }
   const EventRegions& GetEventRegions() const { return mEventRegions; }
   ContainerLayer* GetParent() { return mParent; }
   Layer* GetNextSibling() { return mNextSibling; }
@@ -1511,6 +1528,7 @@ protected:
   gfx::UserData mUserData;
   nsIntRegion mVisibleRegion;
   FrameMetrics mFrameMetrics;
+  FrameMetrics::ViewID mScrollHandoffParentId;
   EventRegions mEventRegions;
   gfx::Matrix4x4 mTransform;
   // A mutation of |mTransform| that we've queued to be applied at the
@@ -1703,22 +1721,6 @@ public:
   void SetAsyncPanZoomController(AsyncPanZoomController *controller);
   AsyncPanZoomController* GetAsyncPanZoomController() const;
 
-  /**
-   * CONSTRUCTION PHASE ONLY
-   * Set the ViewID of the ContainerLayer to which overscroll should be handed
-   * off. A value of NULL_SCROLL_ID means that the default handoff-parent-finding
-   * behaviour should be used (i.e. walk up the layer tree to find the next
-   * scrollable ancestor layer).
-   */
-  void SetScrollHandoffParentId(FrameMetrics::ViewID aScrollParentId)
-  {
-    if (mScrollHandoffParentId != aScrollParentId) {
-      MOZ_LAYERS_LOG_IF_SHADOWABLE(this, ("Layer::Mutated(%p) ScrollHandoffParentId", this));
-      mScrollHandoffParentId = aScrollParentId;
-      Mutated();
-    }
-  }
-
   void SetPreScale(float aXScale, float aYScale)
   {
     if (mPreXScale == aXScale && mPreYScale == aYScale) {
@@ -1776,7 +1778,6 @@ public:
 
   virtual Layer* GetFirstChild() const { return mFirstChild; }
   virtual Layer* GetLastChild() const { return mLastChild; }
-  FrameMetrics::ViewID GetScrollHandoffParentId() const { return mScrollHandoffParentId; }
   float GetPreXScale() const { return mPreXScale; }
   float GetPreYScale() const { return mPreYScale; }
   float GetInheritedXScale() const { return mInheritedXScale; }
@@ -1864,7 +1865,6 @@ protected:
   Layer* mFirstChild;
   Layer* mLastChild;
   nsRefPtr<AsyncPanZoomController> mAPZC;
-  FrameMetrics::ViewID mScrollHandoffParentId;
   float mPreXScale;
   float mPreYScale;
   // The resolution scale inherited from the parent layer. This will already

gfx/layers/apz/src/APZCTreeManager.cpp

@@ -233,7 +233,7 @@ APZCTreeManager::UpdatePanZoomControllerTree(CompositorParent* aCompositor,
 
         apzc->NotifyLayersUpdated(metrics,
                                   aIsFirstPaint && (aLayersId == aOriginatingLayersId));
-        apzc->SetScrollHandoffParentId(container->GetScrollHandoffParentId());
+        apzc->SetScrollHandoffParentId(aLayer->GetScrollHandoffParentId());
 
         // Use the composition bounds as the hit test region.
         // Optionally, the GeckoContentController can provide a touch-sensitive

gfx/layers/ipc/LayerTransactionParent.cpp

@@ -319,6 +319,7 @@ LayerTransactionParent::RecvUpdate(const InfallibleTArray<Edit>& cset,
       layer->SetAnimations(common.animations());
       layer->SetInvalidRegion(common.invalidRegion());
       layer->SetFrameMetrics(common.metrics());
+      layer->SetScrollHandoffParentId(common.scrollParentId());
 
       typedef SpecificLayerAttributes Specific;
       const SpecificLayerAttributes& specific = attrs.specific();
@@ -349,7 +350,6 @@ LayerTransactionParent::RecvUpdate(const InfallibleTArray<Edit>& cset,
         }
         const ContainerLayerAttributes& attrs =
           specific.get_ContainerLayerAttributes();
-        containerLayer->SetScrollHandoffParentId(attrs.scrollParentId());
         containerLayer->SetPreScale(attrs.preXScale(), attrs.preYScale());
         containerLayer->SetInheritedScale(attrs.inheritedXScale(), attrs.inheritedYScale());
         containerLayer->SetBackgroundColor(attrs.backgroundColor().value());

gfx/layers/ipc/LayersMessages.ipdlh

@@ -216,13 +216,13 @@ struct CommonLayerAttributes {
   Animation[] animations;
   nsIntRegion invalidRegion;
   FrameMetrics metrics;
+  ViewID scrollParentId;
 };
 
 struct ThebesLayerAttributes {
   nsIntRegion validRegion;
 };
 struct ContainerLayerAttributes {
-  ViewID scrollParentId;
   float preXScale;
   float preYScale;
   float inheritedXScale;

gfx/layers/ipc/ShadowLayers.cpp

@@ -598,6 +598,7 @@ ShadowLayerForwarder::EndTransaction(InfallibleTArray<EditReply>* aReplies,
     common.animations() = mutant->GetAnimations();
     common.invalidRegion() = mutant->GetInvalidRegion();
     common.metrics() = mutant->GetFrameMetrics();
+    common.scrollParentId() = mutant->GetScrollHandoffParentId();
     attrs.specific() = null_t();
     mutant->FillSpecificAttributes(attrs.specific());