update elements and fix some bugs

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

Index: lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html
diff --git a/lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html b/lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html
index e95a298038e775f03d315d3761e8169837e6ab6c..be64729fbcdee225afad077d141c51b8f336fb0a 100644
--- a/lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html
+++ b/lib/src/iron-a11y-keys-behavior/iron-a11y-keys-behavior.html
@@ -241,7 +241,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
      * `keys` property is pressed.
      *
      * @demo demo/index.html
-     * @polymerBehavior IronA11yKeysBehavior
+     * @polymerBehavior
      */
     Polymer.IronA11yKeysBehavior = {
       properties: {
@@ -255,6 +255,15 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
           }
         },
 
+        /**
+         * 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() {
@@ -398,6 +407,10 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       },
 
       _onKeyBindingEvent: function(keyBindings, event) {
+        if (this.stopKeyboardEventPropagation) {
+          event.stopPropagation();
+        }
+
         keyBindings.forEach(function(keyBinding) {
           var keyCombo = keyBinding[0];
           var handlerName = keyBinding[1];