code: function finalizeMeasurement(id) {
          if (activeTests[id.id]) {
              delete activeTests[id.id];
          }
  
          if (updatableTests[id.id]) {
              delete updatableTests[id.id];
          }
      }
docs: Remove timer from lists so next action starts a new measurement
  
  updateMeasurement may not have been called, so timer may be
  in either or neither list, but should never be in both.
  
  @param {Object} id  Timer id.