Bug 716140 - Create and Send OnStartFrame when a frame starts. r=seth

--HG--
extra : rebase_source : 7af770a5cc28c2a6d199e632c706330a0d582659

image/src/Decoder.cpp

@@ -227,6 +227,11 @@ Decoder::PostFrameStart()
   // reported by the Image.
   NS_ABORT_IF_FALSE(mFrameCount == mImage.GetNumFrames(),
                     "Decoder frame count doesn't match image's!");
+
+  // Fire notifications
+  if (mObserver) {
+    mObserver->OnStartFrame();
+  }
 }
 
 void

image/src/imgDecoderObserver.h

@@ -65,6 +65,13 @@ public:
    */
   virtual void OnStartContainer() = 0;
 
+  /**
+   * Decode notification.
+   *
+   * Called when we know a frame has begun decoding.
+   */
+  virtual void OnStartFrame() = 0;
+
   /**
    * Decode notification.
    *

image/src/imgStatusTracker.cpp

@@ -76,6 +76,18 @@ public:
     }
   }
 
+  virtual void OnStartFrame()
+  {
+    LOG_SCOPE(GetImgLog(), "imgStatusTrackerObserver::OnStartFrame");
+    NS_ABORT_IF_FALSE(mTracker->GetImage(),
+                      "OnStartFrame callback before we've created our image");
+
+    mTracker->RecordStartFrame();
+
+    // This is not observed below the imgStatusTracker level, so we don't need
+    // to SendStartFrame.
+  }
+
   virtual void FrameChanged(const nsIntRect* dirtyRect)
   {
     LOG_SCOPE(GetImgLog(), "imgStatusTrackerObserver::FrameChanged");
@@ -492,6 +504,13 @@ imgStatusTracker::SendStartContainer(imgRequestProxy* aProxy)
     aProxy->OnStartContainer();
 }
 
+void
+imgStatusTracker::RecordStartFrame()
+{
+}
+
+// No SendStartFrame since it's not observed below us.
+
 void
 imgStatusTracker::RecordStopFrame()
 {

image/src/imgStatusTracker.h

@@ -135,6 +135,8 @@ public:
   void SendStartDecode(imgRequestProxy* aProxy);
   void RecordStartContainer(imgIContainer* aContainer);
   void SendStartContainer(imgRequestProxy* aProxy);
+  void RecordStartFrame();
+  // No SendStartFrame since it's not observed below us.
   void RecordFrameChanged(const nsIntRect* aDirtyRect);
   void SendFrameChanged(imgRequestProxy* aProxy, const nsIntRect* aDirtyRect);
   void RecordStopFrame();