message: check for Performance object capabilities
diff: import { Task } from '../task'
  import { isProductionMode } from '../../mol-util/debug';
  -const hasPerformance = typeof performance !== 'undefined'
  +const hasPerformance = (typeof performance !== 'undefined') && performance.mark && performance.measure
  const timingEnabled = hasPerformance && !isProductionMode
  export namespace UserTiming {
  