Use "int" rather than "long" for C++ code interacting with WebIDL's "long".

Source/modules/mediastream/RTCDataChannel.cpp

 /*
  * 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
@@ skipping 128 matching lines @@
     case ReadyStateClosing:
         return "closing";
     case ReadyStateClosed:
         return "closed";
     }
 
     ASSERT_NOT_REACHED();
     return String();
 }
 
-unsigned long RTCDataChannel::bufferedAmount() const
+unsigned RTCDataChannel::bufferedAmount() const
 {
     return m_handler->bufferedAmount();
 }
 
 String RTCDataChannel::binaryType() const
 {
     switch (m_binaryType) {
     case BinaryTypeBlob:
         return "blob";
     case BinaryTypeArrayBuffer:
@@ skipping 168 matching lines @@
 }
 
 void RTCDataChannel::trace(Visitor* visitor)
 {
     visitor->trace(m_scheduledEvents);
     visitor->registerWeakMembers<RTCDataChannel, &RTCDataChannel::clearWeakMembers>(this);
     EventTargetWithInlineData::trace(visitor);
 }
 
 } // namespace blink