function updateUntilDone(globe) {
      // update until the load queue is empty.
      return pollToPromise(function () {
        scene.renderForSpecs();
        return (
          globe._surface._tileLoadQueueHigh.length === 0 &&
          globe._surface._tileLoadQueueMedium.length === 0 &&
          globe._surface._tileLoadQueueLow.length === 0 &&
          globe._surface._debug.tilesWaitingForChildren === 0
        );
      });
    }
Repeatedly calls update until the load queue is empty.  You must wrap any code to follow
this in a "runs" function.