cc: Make sure we don't insert or remove layers during painting

cc/layers/layer.cc

 // Copyright 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layers/layer.h"
 
 #include <algorithm>
 
 #include "base/atomic_sequence_num.h"
 #include "base/location.h"
@@ skipping 117 matching lines @@
   if (layer_tree_host_ == host)
     return;
 
   if (layer_tree_host_) {
     layer_tree_host_->property_trees()->needs_rebuild = true;
     layer_tree_host_->UnregisterLayer(this);
   }
   if (host) {
     host->property_trees()->needs_rebuild = true;
     host->RegisterLayer(this);
+    DCHECK(!host->in_update());

[enne (OOO), 2015/07/10 20:29:21]

Reuse host->in_paint_layer_contents()?

[ajuma, 2015/07/10 20:52:53]

Done, and moved the DCHECK over to LayerTreeHost::{Register, Unregister}Layer.

   }
 
   InvalidatePropertyTreesIndices();
 
   layer_tree_host_ = host;
 
   // When changing hosts, the layer needs to commit its properties to the impl
   // side for the new host.
   SetNeedsPushProperties();
 
@@ skipping 1511 matching lines @@
           ? layer_tree_host()->meta_information_sequence_number()
           : 0;
 }
 
 bool Layer::sorted_for_recursion() {
   return sorted_for_recursion_tracker_ ==
          layer_tree_host()->meta_information_sequence_number();
 }
 
 }  // namespace cc