Reset the root layer on the compositor when recreating a root layer.

ui/compositor/layer_owner.cc

Index: ui/compositor/layer_owner.cc
diff --git a/ui/compositor/layer_owner.cc b/ui/compositor/layer_owner.cc
index cd614b37d8dca3e7e11326c2777d0e72cd80336d..86dd9d6ff7cc39fcb3611c279c88c52471ffa210 100644
--- a/ui/compositor/layer_owner.cc
+++ b/ui/compositor/layer_owner.cc
@@ -66,6 +66,15 @@ scoped_ptr<Layer> LayerOwner::RecreateLayer() {
     new_layer->Add(child);
   }
 
+  ui::Layer* root_layer = old_layer.get();
+  while (root_layer->parent())
+    root_layer = root_layer->parent();

[sadrul, 2015/03/06 14:33:49]

You don't actually need to walk up to the root, right? You can just do:
  bool is_root = !old_layer->parent();
  if (is_root && ...)
    ...

[bruthig, 2015/03/06 15:20:41]

Done.

+
+  // If old_layer was the layer tree root then we need to move the Compositor
+  // over to the new root.
+  if (root_layer == old_layer.get() && old_layer->GetCompositor())
+    old_layer->GetCompositor()->SetRootLayer(new_layer);
+
   // Install the delegate last so that the delegate isn't notified as we copy
   // state to the new layer.
   new_layer->set_delegate(old_delegate);