searchInPath(query, progress) {
    return new Promise(resolve => {
      const requestId = this._manager.registerCallback(innerCallback);
      this._searchService.searchInPath(requestId, this._rootURL, query);

      /**
       * @param {!Array<string>} files
       */
      function innerCallback(files) {
        resolve(files);
        progress.worked(1);
      }
    });
  }
@override
@param {string} query
@param {!Common.Progress} progress
@return {!Promise<!Array<string>>}