Bug 716140 - Handle discarding specially so it gets notified synchronously. r=seth

--HG--
extra : rebase_source : 1bd66dcec4925b486af0905dbd07286bb3ae729e

image/src/RasterImage.cpp

@@ -2504,7 +2504,7 @@ RasterImage::Discard(bool force)
 
   // Notify that we discarded
   if (mStatusTracker)
-    mStatusTracker->GetDecoderObserver()->OnDiscard();
+    mStatusTracker->OnDiscard();
 
   if (force)
     DiscardTracker::Remove(&mDiscardTrackerNode);

image/src/imgStatusTracker.cpp

@@ -849,6 +849,18 @@ imgStatusTracker::OnStopRequest(bool aLastPart,
   }
 }
 
+void
+imgStatusTracker::OnDiscard()
+{
+  RecordDiscard();
+
+  /* notify the kids */
+  nsTObserverArray<imgRequestProxy*>::ForwardIterator iter(mConsumers);
+  while (iter.HasMore()) {
+    SendDiscard(iter.GetNext());
+  }
+}
+
 void
 imgStatusTracker::OnDataAvailable()
 {

image/src/imgStatusTracker.h

@@ -160,6 +160,7 @@ public:
   void OnStartRequest();
   void OnDataAvailable();
   void OnStopRequest(bool aLastPart, nsresult aStatus);
+  void OnDiscard();
 
   /* non-virtual imgIOnloadBlocker methods */
   // NB: If UnblockOnload is sent, and then we are asked to replay the