code: function _tagMatch(match, type) {
          switch (type) {
          case BEZIER:
              match.isBezier = true;
              break;
          case STEP:
              match.isStep = true;
              break;
          }
  
          return match;
      }
docs: Tag this match with type and return it for chaining
  
  @param {!RegExp.match} match  RegExp Match object with steps function parameters
  in array position 1 (and optionally 2).
  @param {number} type Either BEZIER or STEP
  @return {RegExp.match} Same object that was passed in.