update elements and fix some bugs

lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html

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@@ skipping 223 matching lines @@
      *
      * Use the `keyBindings` prototype property to express what combination of keys
      * will trigger the event to fire.
      *
      * Use the `key-event-target` attribute to set up event handlers on a specific
      * node.
      * The `keys-pressed` event will fire when one of the key combinations set with the
      * `keys` property is pressed.
      *
      * @demo demo/index.html
-     * @polymerBehavior IronA11yKeysBehavior
+     * @polymerBehavior
      */
     Polymer.IronA11yKeysBehavior = {
       properties: {
         /**
          * The HTMLElement that will be firing relevant KeyboardEvents.
          */
         keyEventTarget: {
           type: Object,
           value: function() {
             return this;
           }
         },
 
+        /**
+         * If true, this property will cause the implementing element to
+         * automatically stop propagation on any handled KeyboardEvents.
+         */
+        stopKeyboardEventPropagation: {
+          type: Boolean,
+          value: false
+        },
+
         _boundKeyHandlers: {
           type: Array,
           value: function() {
             return [];
           }
         },
 
         // We use this due to a limitation in IE10 where instances will have
         // own properties of everything on the "prototype".
         _imperativeKeyBindings: {
@@ skipping 123 matching lines @@
           keyHandlerTuple = this._boundKeyHandlers.pop();
           keyEventTarget = keyHandlerTuple[0];
           eventName = keyHandlerTuple[1];
           boundKeyHandler = keyHandlerTuple[2];
 
           keyEventTarget.removeEventListener(eventName, boundKeyHandler);
         }
       },
 
       _onKeyBindingEvent: function(keyBindings, event) {
+        if (this.stopKeyboardEventPropagation) {
+          event.stopPropagation();
+        }
+
         keyBindings.forEach(function(keyBinding) {
           var keyCombo = keyBinding[0];
           var handlerName = keyBinding[1];
 
           if (!event.defaultPrevented && keyComboMatchesEvent(keyCombo, event)) {
             this._triggerKeyHandler(keyCombo, handlerName, event);
           }
         }, this);
       },
 
       _triggerKeyHandler: function(keyCombo, handlerName, keyboardEvent) {
         var detail = Object.create(keyCombo);
         detail.keyboardEvent = keyboardEvent;
 
         this[handlerName].call(this, new CustomEvent(keyCombo.event, {
           detail: detail
         }));
       }
     };
   })();
 </script>