Bug 790508: bustage fix r=me

layout/generic/nsFrame.cpp

@@ -986,7 +986,7 @@ nsIFrame::HasOpacity() const
 {
   return GetStyleDisplay()->mOpacity < 1.0f || (mContent &&
            nsLayoutUtils::HasAnimationsForCompositor(mContent,
-                                                     eCSSProperty_opacity)
+                                                     eCSSProperty_opacity) &&
            mContent->GetPrimaryFrame() == this);
 }