[C++11 Allowed Features] Declares a type-safe null pointer converting from NULL to nullptr

cc/animation/animation_registrar.cc

 // Copyright 2012 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/animation/animation_registrar.h"
 
 #include "cc/animation/layer_animation_controller.h"
 
 namespace cc {
 
 AnimationRegistrar::AnimationRegistrar() : supports_scroll_animations_(false) {
 }
 
 AnimationRegistrar::~AnimationRegistrar() {
   AnimationControllerMap copy = all_animation_controllers_;
   for (AnimationControllerMap::iterator iter = copy.begin();
        iter != copy.end();
        ++iter)
-    (*iter).second->SetAnimationRegistrar(NULL);
+    (*iter).second->SetAnimationRegistrar(nullptr);
 }
 
 scoped_refptr<LayerAnimationController>
 AnimationRegistrar::GetAnimationControllerForId(int id) {
   scoped_refptr<LayerAnimationController> to_return;
   if (!ContainsKey(all_animation_controllers_, id)) {
     to_return = LayerAnimationController::Create(id);
     to_return->SetAnimationRegistrar(this);
     all_animation_controllers_[id] = to_return.get();
   } else {
@@ skipping 19 matching lines @@
 }
 
 void AnimationRegistrar::UnregisterAnimationController(
     LayerAnimationController* controller) {
   if (ContainsKey(all_animation_controllers_, controller->id()))
     all_animation_controllers_.erase(controller->id());
   DidDeactivateAnimationController(controller);
 }
 
 }  // namespace cc