cc: Use correct message loop proxy in BlockingTaskRunner

cc/trees/proxy.h

 // 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.
 
 #ifndef CC_TREES_PROXY_H_
 #define CC_TREES_PROXY_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/threading/platform_thread.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "cc/base/cc_export.h"
+#include "cc/trees/blocking_task_runner.h"
 
 namespace base {
 namespace debug {
 class TracedValue;
 }
 class SingleThreadTaskRunner;
 }
 
 namespace gfx {
 class Rect;
@@ skipping 68 matching lines @@
 
   virtual bool SupportsImplScrolling() const = 0;
 
   virtual void AsValueInto(base::debug::TracedValue* value) const = 0;
 
   virtual void SetDebugState(const LayerTreeDebugState& debug_state) = 0;
 
   // Testing hooks
   virtual bool MainFrameWillHappenForTesting() = 0;
 
+  scoped_refptr<BlockingTaskRunner> blocking_main_thread_task_runner() const {

[danakj, 2014/08/28 17:10:46]

could this return a raw pointer?

[Sami, 2014/08/28 18:21:17]

Yep, done.

+    return blocking_main_thread_task_runner_;
+  }
+
  protected:
   Proxy(scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
         scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner);
   friend class DebugScopedSetImplThread;
   friend class DebugScopedSetMainThread;
   friend class DebugScopedSetMainThreadBlocked;
 
  private:
   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner_;
+  scoped_refptr<BlockingTaskRunner> blocking_main_thread_task_runner_;
+
 #if DCHECK_IS_ON
   const base::PlatformThreadId main_thread_id_;
   bool impl_thread_is_overridden_;
   bool is_main_thread_blocked_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(Proxy);
 };
 
 #if DCHECK_IS_ON
@@ skipping 17 matching lines @@
   explicit DebugScopedSetMainThreadBlocked(Proxy* proxy) {}
   ~DebugScopedSetMainThreadBlocked() {}
  private:
   DISALLOW_COPY_AND_ASSIGN(DebugScopedSetMainThreadBlocked);
 };
 #endif
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROXY_H_