retry() {
    if (!this.hasReachedMaxRetries()) {
      this.increaseAttemptCount();
      this.imageLoader_.removeImage(this.id_);
      // Postpone starting a new request in case we are within an event handler
      // for an image load error.
      setTimeout(goog.bind(this.start_, this), 0);
      return true;
    } else {
      return false;
    }
  }
Sets up a request to fetch images if the retry count has not been reached.
@return {boolean} Whether a retry attempt was started.