Clean up forward declarations in Source/platform

Source/platform/network/SocketStreamHandleClient.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2011, 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 16 matching lines @@
  * 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 SocketStreamHandleClient_h
 #define SocketStreamHandleClient_h
 
 namespace blink {
 
-class KURL;
 class SocketStreamError;
 class SocketStreamHandle;
 
 class SocketStreamHandleClient : public GarbageCollectedMixin {
 public:
     virtual ~SocketStreamHandleClient() { }
 
     virtual void didOpenSocketStream(SocketStreamHandle*) { }
     virtual void didCloseSocketStream(SocketStreamHandle*) { }
     virtual void didReceiveSocketStreamData(SocketStreamHandle*, const char* /*data*/, int /*length*/) { }
     virtual void didConsumeBufferedAmount(SocketStreamHandle*, size_t consumed) { }
 
     virtual void didFailSocketStream(SocketStreamHandle*, const SocketStreamError&) { }
 
     virtual void trace(Visitor*) { }
 };
 
 } // namespace blink
 
 #endif // SocketStreamHandleClient_h