code: function(a, el, sType, fn) {
                  for (var i=0, l=a.length; i<l; i=i+1) {
                      var li = a[i];
                      if ( li                 && 
                           li[this.FN] == fn  && 
                           li[this.EL] == el  && 
                           li[this.TYPE] == sType ) {
                          return i;
                      }
                  }
  
                  return -1;
              }
docs: Locating the saved event handler data by function ref
  
  @method _getCacheIndex
  @static
  @private