Move platform_thread to base/threading and put in the base namespace. I left ...

base/lock.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 BASE_LOCK_H_
 #define BASE_LOCK_H_
 #pragma once
 
 #include "base/lock_impl.h"
-#include "base/platform_thread.h"
+#include "base/threading/platform_thread.h"
 
 // A convenient wrapper for an OS specific critical section.  The only real
 // intelligence in this class is in debug mode for the support for the
 // AssertAcquired() method.
 
 class Lock {
  public:
 #if defined(NDEBUG)             // Optimized wrapper implementation
   Lock() : lock_() {}
   ~Lock() {}
@@ skipping 52 matching lines @@
   // It's worth it to share the code.
   void CheckHeldAndUnmark();
   void CheckUnheldAndMark();
 
   // All private data is implicitly protected by lock_.
   // Be VERY careful to only access members under that lock.
 
   // Determines validity of owning_thread_id_.  Needed as we don't have
   // a null owning_thread_id_ value.
   bool owned_by_thread_;
-  PlatformThreadId owning_thread_id_;
+  base::PlatformThreadId owning_thread_id_;
 #endif  // NDEBUG
 
   LockImpl lock_;  // Platform specific underlying lock implementation.
 
   DISALLOW_COPY_AND_ASSIGN(Lock);
 };
 
 // A helper class that acquires the given Lock while the AutoLock is in scope.
 class AutoLock {
  public:
@@ skipping 24 matching lines @@
   ~AutoUnlock() {
     lock_.Acquire();
   }
 
  private:
   Lock& lock_;
   DISALLOW_COPY_AND_ASSIGN(AutoUnlock);
 };
 
 #endif  // BASE_LOCK_H_