[cc] Change semantics of fixed-pos container layer

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index baf32a383e384dbf353e395d3fddba174fa774bf..71d806068930f49d99a48b9d2b5db349b6dd398d 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -1156,7 +1156,7 @@ void LayerTreeHost::PushPropertiesTo(LayerTreeImpl* tree_impl) {
         page_scale_layer_->id(), inner_viewport_scroll_layer_->id(),
         outer_viewport_scroll_layer_ ? outer_viewport_scroll_layer_->id()
                                      : Layer::INVALID_ID);
-    DCHECK(inner_viewport_scroll_layer_->IsContainerForFixedPositionLayers());
+    DCHECK(page_scale_layer_->IsContainerForFixedPositionLayers());

[bokan, 2017/04/26 21:17:56]

I think this DCHECK should be for the outer container layer.

   } else {
     tree_impl->ClearViewportLayers();
   }