[WebSocket] bufferedAmount should not decrease inside a task.

public/web/WebSocket.h

 /*
  * Copyright (C) 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 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 WebSocket_h
 #define WebSocket_h
 
 #include "../platform/WebCommon.h"
 #include "../platform/WebPrivatePtr.h"
+#include "../platform/WebString.h"
 
 namespace WebCore { class WebSocketChannel; }
 
 namespace blink {
 
 class WebArrayBuffer;
 class WebDocument;
-class WebString;
 class WebURL;
 class WebSocketClient;
 
 class WebSocket {
 public:
     enum CloseEventCode {
         CloseEventCodeNotSpecified = -1,
         CloseEventCodeNormalClosure = 1000,
         CloseEventCodeGoingAway = 1001,
         CloseEventCodeProtocolError = 1002,
@@ skipping 23 matching lines @@
     // specification. It specifies binary object type for receiving binary
     // frames representation. Receiving text frames are always mapped to
     // WebString type regardless of this attribute.
     // Default type is BinaryTypeBlob. But currently it is not supported.
     // Set BinaryTypeArrayBuffer here ahead of using binary communication.
     // See also, The WebSocket API - http://www.w3.org/TR/websockets/ .
     virtual BinaryType binaryType() const = 0;
     virtual bool setBinaryType(BinaryType) = 0;
 
     virtual void connect(const WebURL&, const WebString& protocol) = 0;
-    virtual WebString subprotocol() = 0;
-    virtual WebString extensions() = 0;
+    virtual WebString subprotocol() { return WebString(); }
+    virtual WebString extensions() { return WebString(); }
     virtual bool sendText(const WebString&) = 0;
     virtual bool sendArrayBuffer(const WebArrayBuffer&) = 0;
-    virtual unsigned long bufferedAmount() const = 0;
+    virtual unsigned long bufferedAmount() const { return 0; }
     virtual void close(int code, const WebString& reason) = 0;
     virtual void fail(const WebString& reason) = 0;
     virtual void disconnect() = 0;
 };
 
 } // namespace blink
 
 #endif // WebSocket_h