code: function createPerfMeasurement(id, name) {
          var pm = new PerfMeasurement(id, name);
          exports[id] = pm;
  
          return pm;
      }
docs: Create a new PerfMeasurement key. Adds itself to the module export.
  Can be accessed on the module, e.g. PerfUtils.MY_PERF_KEY.
  
  @param {!string} id Unique ID for this measurement name
  @param {!name} name A short name for this measurement