Bug 790505, part 2: Add API for scheduling a shadowable-layer mutation to be applied at the next layers transaction. r=mattwoodrow,roc

gfx/layers/basic/BasicLayerManager.cpp

@@ -867,6 +867,8 @@ BasicLayerManager::PaintLayer(gfxContext* aTarget,
 
   RenderTraceScope trace("BasicLayerManager::PaintLayer", "707070");
 
+  aLayer->ApplyPendingUpdatesForThisTransaction();
+
   const nsIntRect* clipRect = aLayer->GetEffectiveClipRect();
   // aLayer might not be a container layer, but if so we take care not to use
   // the container variable