Backed out changeset 376c45f4d905 (bug 1022612)

layout/base/nsDisplayList.cpp

@@ -1737,10 +1737,8 @@ nsDisplayItem::RecomputeVisibility(nsDisplayListBuilder* aBuilder,
   // When we recompute visibility within layers we don't need to
   // expand the visible region for content behind plugins (the plugin
   // is not in the layer).
-  if (!ComputeVisibility(aBuilder, aVisibleRegion, nsRect())) {
-    mVisibleRect = nsRect();
+  if (!ComputeVisibility(aBuilder, aVisibleRegion, nsRect()))
     return false;
-  }
 
   nsRegion opaque = TreatAsOpaque(this, aBuilder);
   aBuilder->SubtractFromVisibleRegion(aVisibleRegion, opaque);