Bug 483841. Animated background images on visibility:hidden elements shouldn't cause any painting. r+sr=dbaron

--HG--
extra : rebase_source : de0ca0f1c37e7a47229f69ec1b375dd5c3202bb0

layout/base/nsImageLoader.cpp

@@ -254,5 +254,7 @@ nsImageLoader::RedrawDirtyFrame(const nsRect* aDamageRect)
 
 #endif
 
-  mFrame->Invalidate(bounds);
+  if (mFrame->GetStyleVisibility()->IsVisible()) {
+    mFrame->Invalidate(bounds);
+  }
 }