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

base/threading/thread_checker_unittest.cc

 // 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.
 
 #include "base/basictypes.h"
 #include "base/logging.h"
-#include "base/thread_checker.h"
 #include "base/scoped_ptr.h"
+#include "base/threading/thread_checker.h"
 #include "base/threading/simple_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #ifndef NDEBUG
 
+namespace base {
+
 // Simple class to exersice the basics of ThreadChecker.
 // Both the destructor and DoStuff should verify that they were
 // called on the same thread as the constructor.
 class ThreadCheckerClass : public ThreadChecker {
  public:
   ThreadCheckerClass() {}
 
   // Verifies that it was called on the same thread as the constructor.
   void DoStuff() {
     DCHECK(CalledOnValidThread());
@@ skipping 108 matching lines @@
       call_on_thread.Start();
       call_on_thread.Join();
 
       // Verify that DoStuff asserts after moving to another thread.
       thread_checker_class->DoStuff();
     }, "");
 }
 
 #endif  // GTEST_HAS_DEATH_TEST
 
+}  // namespace base
+
 #endif  // NDEBUG