[sync] Replace MessageLoopProxy usage with ThreadTaskRunnerHandle

sync/internal_api/public/util/weak_handle.h

 // 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.
 
 // Weak handles provides a way to refer to weak pointers from another
 // thread.  This is useful because it is not safe to reference a weak
 // pointer from a thread other than the thread on which it was
 // created.
 //
 // Weak handles can be passed across threads, so for example, you can
@@ skipping 40 matching lines @@
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback_forward.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/single_thread_task_runner.h"
 #include "sync/base/sync_export.h"
 
-namespace base {
-class MessageLoopProxy;
-}  // namespace base
-
 namespace tracked_objects {
 class Location;
 }  // namespace tracked_objects
 
 namespace syncer {
 
 template <typename T> class WeakHandle;
 
 namespace internal {
 // These classes are part of the WeakHandle implementation.  DO NOT
@@ skipping 34 matching lines @@
  protected:
   // May be destroyed on any thread.
   ~WeakHandleCoreBase();
 
   // May be called on any thread.
   void PostToOwnerThread(const tracked_objects::Location& from_here,
                          const base::Closure& fn) const;
 
  private:
   // May be used on any thread.
-  const scoped_refptr<base::MessageLoopProxy> owner_loop_proxy_;
+  const scoped_refptr<base::SingleThreadTaskRunner> owner_loop_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(WeakHandleCoreBase);
 };
 
 // WeakHandleCore<T> contains all the logic for WeakHandle<T>.
 template <typename T>
 class WeakHandleCore
     : public WeakHandleCoreBase,
       public base::RefCountedThreadSafe<WeakHandleCore<T> > {
  public:
@@ skipping 238 matching lines @@
 
 // Makes a WeakHandle from a WeakPtr.
 template <typename T>
 WeakHandle<T> MakeWeakHandle(const base::WeakPtr<T>& ptr) {
   return WeakHandle<T>(ptr);
 }
 
 }  // namespace syncer
 
 #endif  // SYNC_UTIL_WEAK_HANDLE_H_