code: protected void queueClipFailure (final ClipBuffer buffer)
      {
          _rqueue.postRunnable(new Runnable() {
              public void run () {
                  _loading.remove(buffer.getKey());
                  buffer.failed();
              }
          });
      }
docs: Queues the supplied clip buffer up using our {@link RunQueue} to notify its observers that
  it failed to load.