Method runPromise

src/service/vsync-impl.js:187–195

* Runs vsync task: measure followed by mutate. Returns the promise that * will be resolved as soon as the task has been completed. * * If state is not provided, the value passed to the measure and mutate * will be undefined. * * @param {!VsyncTaskSpecDef} task * @param {!VsyncSt

(task, opt_state)

   * @return {!Promise}
   */
  runPromise(task, opt_state) {
    this.run(task, opt_state);
    if (this.nextFramePromise_) {
      return this.nextFramePromise_;
    }
    const deferred = new Deferred();
    this.nextFrameResolver_ = deferred.resolve;
    return (this.nextFramePromise_ = deferred.promise);
  }

  /**
   * Creates a function that will call {@link run} method.