shadows/framework/src/main/java/org/robolectric/shadows/ShadowLegacyLooper.java
@Override
  @Deprecated
  public boolean postAtFrontOfQueue(Runnable runnable) {
    if (!quit) {
      getScheduler().postAtFrontOfQueue(runnable);
      return true;
    } else {
      return false;
    }
  }
@Override
  @Deprecated
  public boolean postAtFrontOfQueue(Runnable runnable) {
    if (!quit) {
      getScheduler().postAtFrontOfQueue(runnable);
      return true;
    } else {
      return false;
    }
  }
@ Override @ Deprecated public boolean postAtFrontOfQueue ( Runnable runnable ) { if ( ! quit ) { getScheduler ( ) . postAtFrontOfQueue ( runnable ) ; return true ; } else { return false ; } }
Enqueue a task to be run ahead of all other delayed tasks.

@param runnable    the task to be run
@return true if the runnable is enqueued
@see android.os.Handler#postAtFrontOfQueue(Runnable)
@deprecated Use a {@link android.os.Handler} instance to post to a looper.
Enqueue a task to be run ahead of all other delayed tasks .