Modify ThreadChecker and NonThreadSafe so that their functionality is

net/url_request/url_request_throttler_manager.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 NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_
 #define NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/scoped_ptr.h"
 #include "base/singleton.h"
-#include "base/synchronization/lock.h"  // ThreadCheckerForRelease
-#include "base/threading/platform_thread.h"  // ThreadCheckerForRelease
+#include "base/threading/thread_checker_impl.h"
 #include "googleurl/src/gurl.h"
 #include "net/url_request/url_request_throttler_entry.h"
 
 namespace net {
 
-// TODO(joi): Delete this temporary copy of base::ThreadChecker (needed to
-// enable it in release builds) and go back to simply inheriting from
-// NonThreadSafe once crbug.com/71721 has been tracked down.
-class ThreadCheckerForRelease {
- public:
-  ThreadCheckerForRelease();
-  ~ThreadCheckerForRelease();
-
-  bool CalledOnValidThread() const;
-
-  // Changes the thread that is checked for in CalledOnValidThread.  This may
-  // be useful when an object may be created on one thread and then used
-  // exclusively on another thread.
-  void DetachFromThread();
-
- private:
-  void EnsureThreadIdAssigned() const;
-
-  mutable base::Lock lock_;
-  // This is mutable so that CalledOnValidThread can set it.
-  // It's guarded by |lock_|.
-  mutable base::PlatformThreadId valid_thread_id_;
-};
-
 // Class that registers URL request throttler entries for URLs being accessed
 // in order to supervise traffic. URL requests for HTTP contents should
 // register their URLs in this manager on each request.
 //
 // URLRequestThrottlerManager maintains a map of URL IDs to URL request
 // throttler entries. It creates URL request throttler entries when new URLs
 // are registered, and does garbage collection from time to time in order to
 // clean out outdated entries. URL ID consists of lowercased scheme, host, port
 // and path. All URLs converted to the same ID will share the same entry.
 //
@@ skipping 89 matching lines @@
   bool enforce_throttling_;
 
   // Certain tests do not obey the net component's threading policy, so we
   // keep track of whether we're being used by tests, and turn off certain
   // checks.
   //
   // TODO(joi): See if we can fix the offending unit tests and remove this
   // workaround.
   bool being_tested_;
 
-  ThreadCheckerForRelease thread_checker_;
+  base::ThreadCheckerImpl thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(URLRequestThrottlerManager);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_THROTTLER_MANAGER_H_