code: function _getMatcher (element) {
    if (_matcher) {
      return _matcher;
    }
  
    if (element.matches) {
      _matcher = element.matches;
      return _matcher;
    }
  
    if (element.webkitMatchesSelector) {
      _matcher = element.webkitMatchesSelector;
      return _matcher;
    }
  
    if (element.mozMatchesSelector) {
      _matcher = element.mozMatchesSelector;
      return _matcher;
    }
  
    if (element.msMatchesSelector) {
      _matcher = element.msMatchesSelector;
      return _matcher;
    }
  
    if (element.oMatchesSelector) {
      _matcher = element.oMatchesSelector;
      return _matcher;
    }
  
    // if it doesn't match a native browser method
    // fall back to the delegator function
    _matcher = Delegator.matchesSelector;
    return _matcher;
  }
docs: returns function to use for determining if an element
  matches a query selector
  
  @returns {Function}