code: public BUILDER setFirstAvailableImageRequests(
        REQUEST[] firstAvailableImageRequests,
        boolean tryCacheOnlyFirst) {
      Preconditions.checkArgument(
          firstAvailableImageRequests == null || firstAvailableImageRequests.length > 0,
          "No requests specified!");
      mMultiImageRequests = firstAvailableImageRequests;
      mTryCacheOnlyFirst = tryCacheOnlyFirst;
      return getThis();
    }
docs: Sets the array of first-available image requests that will be probed in order.
  <p> For performance reasons, the array is not deep-copied, but only stored by reference.
  Please don't modify once submitted.
  
  @param tryCacheOnlyFirst if set, bitmap cache only requests will be tried in order before
  the supplied requests.