code: function logTypeToString(logType) {
  	var logTypeString;
  	if (logType instanceof RegExp) {
  		logTypeString = logType.source;
  	} else if (typeof (logType) === 'string') {
  		logTypeString = '^' + JSUtils.escapeRegExp(logType) + '$';
  	} else {
  		throw new Error('logType is neither a regular expression nor a string.');
  	}
  	return logTypeString;
  }
docs: Convert logType into a source string for a regExp that we can
  subsequently use to test logTypes passed in from Logger.log.
  @param {RegExp} logType
  @return {string}
  @private