Reduce platform/heap/ wtf includes.

Source/platform/heap/ThreadState.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 16 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef ThreadState_h
 #define ThreadState_h
 
 #include "platform/PlatformExport.h"
 #include "platform/heap/AddressSanitizer.h"
 #include "public/platform/WebThread.h"
+#include "wtf/Forward.h"
 #include "wtf/HashMap.h"
 #include "wtf/HashSet.h"
-#include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/ThreadSpecific.h"
 #include "wtf/Threading.h"
 #include "wtf/ThreadingPrimitives.h"
-#include "wtf/Vector.h"
-#include "wtf/text/StringHash.h"
 #include "wtf/text/WTFString.h"
 
 namespace v8 {
 class Isolate;
 };
 
 namespace blink {
 
 class BasePage;
 class CallbackStack;
@@ skipping 719 matching lines @@
         m_locked = false;
     }
 
     MutexBase& m_mutex;
     bool m_locked;
 };
 
 } // namespace blink
 
 #endif // ThreadState_h