code: void finish(final String tag) {
          if (mRequestQueue != null) {
              mRequestQueue.finish(this);
          }
          if (MarkerLog.ENABLED) {
              final long threadId = Thread.currentThread().getId();
  
              mEventLog.add(tag, threadId);
              mEventLog.finish(this.toString());
          }
      }
docs: Notifies the request queue that this request has finished (successfully or with error).
  
  <p>Also dumps all events from this request's event log; for debugging.</p>