code: public Bundle stopTiming(String label) {
          addIteration(label);
          if (mPerfWriter != null)
              mPerfWriter.writeStopTiming(mPerfMeasurement);
          return mPerfMeasurement;
      }
docs: Stop measurement of user and cpu time.
  
  @param label description of code block between addIteration or
  startTiming and stopTiming, used to label output
  @return Runtime metrics stored in a bundle, including all iterations
  between calls to startTiming and stopTiming. List of iterations
  is keyed by {@link #METRIC_KEY_ITERATIONS iterations}.