Bug 1137875 - Have the SharedFrameMetricsData hold a copy of the layers id. r=nical

gfx/layers/apz/src/AsyncPanZoomController.cpp

@@ -3098,7 +3098,7 @@ void AsyncPanZoomController::ShareCompositorFrameMetrics() {
       // Send the shared memory handle and cross process handle to the content
       // process by an asynchronous ipc call. Include the APZC unique ID
       // so the content process know which APZC sent this shared FrameMetrics.
-      if (!compositor->SendSharedCompositorFrameMetrics(mem, handle, mAPZCId)) {
+      if (!compositor->SendSharedCompositorFrameMetrics(mem, handle, mLayersId, mAPZCId)) {
         APZC_LOG("%p failed to share FrameMetrics with content process.", this);
       }
     }

gfx/layers/ipc/CompositorChild.cpp

@@ -339,9 +339,11 @@ bool
 CompositorChild::RecvSharedCompositorFrameMetrics(
     const mozilla::ipc::SharedMemoryBasic::Handle& metrics,
     const CrossProcessMutexHandle& handle,
+    const uint64_t& aLayersId,
     const uint32_t& aAPZCId)
 {
-  SharedFrameMetricsData* data = new SharedFrameMetricsData(metrics, handle, aAPZCId);
+  SharedFrameMetricsData* data = new SharedFrameMetricsData(
+    metrics, handle, aLayersId, aAPZCId);
   mFrameMetricsTable.Put(data->GetViewID(), data);
   return true;
 }
@@ -364,9 +366,11 @@ CompositorChild::RecvReleaseSharedCompositorFrameMetrics(
 CompositorChild::SharedFrameMetricsData::SharedFrameMetricsData(
     const ipc::SharedMemoryBasic::Handle& metrics,
     const CrossProcessMutexHandle& handle,
-    const uint32_t& aAPZCId) :
-    mMutex(nullptr),
-    mAPZCId(aAPZCId)
+    const uint64_t& aLayersId,
+    const uint32_t& aAPZCId)
+  : mMutex(nullptr)
+  , mLayersId(aLayersId)
+  , mAPZCId(aAPZCId)
 {
   mBuffer = new ipc::SharedMemoryBasic(metrics);
   mBuffer->Map(sizeof(FrameMetrics));
@@ -403,6 +407,12 @@ CompositorChild::SharedFrameMetricsData::GetViewID()
   return frame->GetScrollId();
 }
 
+uint64_t
+CompositorChild::SharedFrameMetricsData::GetLayersId() const
+{
+  return mLayersId;
+}
+
 uint32_t
 CompositorChild::SharedFrameMetricsData::GetAPZCId()
 {

gfx/layers/ipc/CompositorChild.h

@@ -128,6 +128,7 @@ private:
 
   virtual bool RecvSharedCompositorFrameMetrics(const mozilla::ipc::SharedMemoryBasic::Handle& metrics,
                                                 const CrossProcessMutexHandle& handle,
+                                                const uint64_t& aLayersId,
                                                 const uint32_t& aAPZCId) MOZ_OVERRIDE;
 
   virtual bool RecvReleaseSharedCompositorFrameMetrics(const ViewID& aId,
@@ -142,12 +143,14 @@ private:
     SharedFrameMetricsData(
         const mozilla::ipc::SharedMemoryBasic::Handle& metrics,
         const CrossProcessMutexHandle& handle,
+        const uint64_t& aLayersId,
         const uint32_t& aAPZCId);
 
     ~SharedFrameMetricsData();
 
     void CopyFrameMetrics(FrameMetrics* aFrame);
     FrameMetrics::ViewID GetViewID();
+    uint64_t GetLayersId() const;
     uint32_t GetAPZCId();
 
   private:
@@ -155,6 +158,7 @@ private:
     // the shared FrameMetrics
     nsRefPtr<mozilla::ipc::SharedMemoryBasic> mBuffer;
     CrossProcessMutex* mMutex;
+    uint64_t mLayersId;
     // Unique ID of the APZC that is sharing the FrameMetrics
     uint32_t mAPZCId;
   };

gfx/layers/ipc/PCompositor.ipdl

@@ -133,7 +133,7 @@ parent:
 child:
   // Send back Compositor Frame Metrics from APZCs so tiled layers can
   // update progressively.
-  async SharedCompositorFrameMetrics(Handle metrics, CrossProcessMutexHandle mutex, uint32_t aAPZCId);
+  async SharedCompositorFrameMetrics(Handle metrics, CrossProcessMutexHandle mutex, uint64_t aLayersId, uint32_t aAPZCId);
   async ReleaseSharedCompositorFrameMetrics(ViewID aId, uint32_t aAPZCId);
 };