No need for a header to include itself.

Source/core/platform/mediastream/RTCDataChannelHandler.h

 /*
  * Copyright (C) 2012 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (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 RTCDataChannelHandler_h
 #define RTCDataChannelHandler_h
 
-#include "core/platform/mediastream/RTCDataChannelHandler.h"
 #include "core/platform/mediastream/RTCDataChannelHandlerClient.h"
 #include "public/platform/WebRTCDataChannelHandler.h"
 #include "public/platform/WebRTCDataChannelHandlerClient.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace WebCore {
 
 class RTCDataChannelHandlerClient;
 
@@ skipping 30 matching lines @@
 private:
     explicit RTCDataChannelHandler(blink::WebRTCDataChannelHandler*);
 
     OwnPtr<blink::WebRTCDataChannelHandler> m_webHandler;
     RTCDataChannelHandlerClient* m_client;
 };
 
 } // namespace WebCore
 
 #endif // RTCDataChannelHandler_h