FBTF: Remove unneeded headers from base/ (part 9)

chrome/browser/sync/util/channel.h

 // Copyright (c) 2010 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 CHROME_BROWSER_SYNC_UTIL_CHANNEL_H_
 #define CHROME_BROWSER_SYNC_UTIL_CHANNEL_H_
 #pragma once
 
 ///////////////////////////////////////////////////////////////////////////////
 //
@@ skipping 34 matching lines @@
 //
 //    private:
 //     Channel<FooEvent> channel_;
 //   };
 //
 //
 ///////////////////////////////////////////////////////////////////////////////
 
 #include "base/lock.h"
 #include "base/observer_list.h"
+#include "base/platform_thread.h"
 
 namespace browser_sync {
 
 template <typename EventType>
 class Channel;
 
 class EventHandler {
 };
 
 template <typename EventType>
@@ skipping 70 matching lines @@
 
  private:
   Lock event_handlers_mutex_;
   PlatformThreadId locking_thread_;
   ObserverList<EventHandler> event_handlers_;
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_UTIL_CHANNEL_H_