Rewrite scoped_ptr<T>(NULL) to use the default ctor in cc/.

cc/test/layer_tree_test.cc

 // Copyright 2011 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/test/layer_tree_test.h"
 
 #include "base/command_line.h"
 #include "cc/animation/animation.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/animation/layer_animation_controller.h"
@@ skipping 278 matching lines @@
 LayerTreeTest::LayerTreeTest()
     : beginning_(false),
       end_when_begin_returns_(false),
       timed_out_(false),
       scheduled_(false),
       schedule_when_set_visible_true_(false),
       started_(false),
       ended_(false),
       delegating_renderer_(false),
       timeout_seconds_(0),
-      impl_thread_(NULL),
       weak_factory_(this) {
   main_thread_weak_ptr_ = weak_factory_.GetWeakPtr();
 
   // Tests should timeout quickly unless --cc-layer-tree-test-no-timeout was
   // specified (for running in a debugger).
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (!command_line->HasSwitch(switches::kCCLayerTreeTestNoTimeout))
     timeout_seconds_ = 5;
 }
 
@@ skipping 60 matching lines @@
 void LayerTreeTest::PostSetVisibleToMainThread(bool visible) {
   proxy()->MainThread()->PostTask(
       base::Bind(&LayerTreeTest::DispatchSetVisible,
                  main_thread_weak_ptr_,
                  visible));
 }
 
 void LayerTreeTest::DoBeginTest() {
   client_ = LayerTreeHostClientForTesting::Create(this);
 
-  scoped_ptr<cc::Thread> impl_ccthread(NULL);
+  scoped_ptr<cc::Thread> impl_ccthread;
   if (impl_thread_) {
     impl_ccthread = cc::ThreadImpl::CreateForDifferentThread(
         impl_thread_->message_loop_proxy());
   }
   layer_tree_host_ = LayerTreeHostForTesting::Create(this,
                                                      client_.get(),
                                                      settings_,
                                                      impl_ccthread.Pass());
   ASSERT_TRUE(layer_tree_host_);
 
@@ skipping 208 matching lines @@
 
 scoped_refptr<cc::ContextProvider> LayerTreeTest::
     OffscreenContextProviderForCompositorThread() {
   if (!compositor_thread_contexts_.get() ||
       compositor_thread_contexts_->DestroyedOnMainThread())
     compositor_thread_contexts_ = FakeContextProvider::Create();
   return compositor_thread_contexts_;
 }
 
 }  // namespace cc