Implement new websocket handshake based on draft-hixie-thewebsocketprotocol-76

BUG=none
TEST=net_unittests passes

Review URL: http://codereview.chromium.org/1108002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@42736 0039d316-1c4b-4281-b951-d872f2087c98
  void SetOnOpen(Callback1<WebSocketEvent*>::Type* callback) {
    onopen_ = callback;
  }

  void SetOnOpen(Callback1<WebSocketEvent*>::Type* callback) {
    onopen_ = callback;
  }
