cc: Remove use of PassAs() and constructor-casting with scoped_ptr.

cc/resources/texture_mailbox_deleter_unittest.cc

 // Copyright 2013 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/resources/texture_mailbox_deleter.h"
 
 #include "base/message_loop/message_loop_proxy.h"
 #include "cc/resources/single_release_callback.h"
 #include "cc/test/test_context_provider.h"
 #include "cc/test/test_web_graphics_context_3d.h"
@@ skipping 16 matching lines @@
   EXPECT_TRUE(context_provider->HasOneRef());
   EXPECT_EQ(1u, context_provider->TestContext3d()->NumTextures());
 
   scoped_ptr<SingleReleaseCallback> cb =
       deleter->GetReleaseCallback(context_provider, texture_id).Pass();
   EXPECT_FALSE(context_provider->HasOneRef());
   EXPECT_EQ(1u, context_provider->TestContext3d()->NumTextures());
 
   // When the deleter is destroyed, it immediately drops its ref on the
   // ContextProvider, and deletes the texture.
-  deleter.reset();
+  deleter = nullptr;
   EXPECT_TRUE(context_provider->HasOneRef());
   EXPECT_EQ(0u, context_provider->TestContext3d()->NumTextures());
 
   // Run the scoped release callback before destroying it, but it won't do
   // anything.
   cb->Run(0, false);
 }
 
 }  // namespace
 }  // namespace cc