Update libjingle to 50191337.

R=mallinath@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/1885005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@4461 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/app/webrtc/datachannelinterface.h

@@ -75,6 +75,8 @@ struct DataBuffer {
       : data(text.data(), text.length()),
         binary(false) {
   }
+  size_t size() const { return data.length(); }
+
   talk_base::Buffer data;
   // Indicates if the received data contains UTF-8 or binary data.
   // Note that the upper layers are left to verify the UTF-8 encoding.