Delete Tracked, and move Location to its own file.

base/observer_list_threadsafe.h

 // Copyright (c) 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 BASE_OBSERVER_LIST_THREADSAFE_H_
 #define BASE_OBSERVER_LIST_THREADSAFE_H_
 #pragma once
 
 #include <algorithm>
 #include <map>
 
 #include "base/basictypes.h"
 #include "base/callback_old.h"
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
 #include "base/observer_list.h"
 #include "base/task.h"
 
 ///////////////////////////////////////////////////////////////////////////////
 //
 // OVERVIEW:
@@ skipping 239 matching lines @@
   typedef std::map<MessageLoop*, ObserverListContext*> ObserversListMap;
 
   base::Lock list_lock_;  // Protects the observer_lists_.
   ObserversListMap observer_lists_;
   const NotificationType type_;
 
   DISALLOW_COPY_AND_ASSIGN(ObserverListThreadSafe);
 };
 
 #endif  // BASE_OBSERVER_LIST_THREADSAFE_H_