static ScheduledExecutorService get() {
      if (sJobStarterExecutor == null) {
        sJobStarterExecutor = Executors.newSingleThreadScheduledExecutor();
      }
      return sJobStarterExecutor;
    }
Manages jobs so that only one can be executed at a time and no more often than once in <code>
mMinimumJobIntervalMs</code> milliseconds.
imagepipeline/src/main/java/com/facebook/imagepipeline/producers/JobScheduler.java