add DOMTokenList polyfill (ad-hoc: directly in g-component)

src/g-component.html

@@ -11,6 +11,27 @@ license that can be found in the LICENSE file.
     });
   </script>
   <script>
+    // polyfill for DOMTokenList features: list of classes in add/remove; 
+    // enable method.
+    (function() {
+      'use strict';
+      var add = DOMTokenList.prototype.add;
+      var remove = DOMTokenList.prototype.remove;
+      DOMTokenList.prototype.add = function() {
+        for (var i = 0; i < arguments.length; i++) {
+         add.call(this, arguments[i]);
+        }
+      };
+      DOMTokenList.prototype.remove = function() {
+        for (var i = 0; i < arguments.length; i++) {
+         remove.call(this, arguments[i]);
+        }
+      };
+      DOMTokenList.prototype.enable = function(name, value) {
+        value ? this.add(name) : this.remove(name);
+      };
+    })();
+    
     (function(){
       var bindAttrs = function(inAttrs) {
         inAttrs.forEach(function(a) {