update elements and fix some bugs

lib/src/paper-behaviors/paper-inky-focus-behavior.html

Index: lib/src/paper-behaviors/paper-inky-focus-behavior.html
diff --git a/lib/src/paper-behaviors/paper-inky-focus-behavior.html b/lib/src/paper-behaviors/paper-inky-focus-behavior.html
index 4f6e9f8933c12202e94cc90e35660c01a7ba8505..76fffc116baf351c2bec4f627c9e547c626e2935 100644
--- a/lib/src/paper-behaviors/paper-inky-focus-behavior.html
+++ b/lib/src/paper-behaviors/paper-inky-focus-behavior.html
@@ -10,6 +10,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
 <link rel="import" href="../polymer/polymer.html">
 <link rel="import" href="../iron-behaviors/iron-button-state.html">
+<link rel="import" href="paper-ripple-behavior.html">
 
 <script>
 
@@ -25,11 +26,20 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     ],
 
     _focusedChanged: function(receivedFocusFromKeyboard) {
-      if (!this.$.ink) {
-        return;
+      if (receivedFocusFromKeyboard) {
+        this.ensureRipple();
       }
-
-      this.$.ink.holdDown = receivedFocusFromKeyboard;
+      if (this.hasRipple()) {
+        this._ripple.holdDown = receivedFocusFromKeyboard;
+      }
+    },
+
+    _createRipple: function() {
+      var ripple = Polymer.PaperRippleBehavior._createRipple();
+      ripple.id = 'ink';
+      ripple.setAttribute('center', '');
+      ripple.classList.add('circle');
+      return ripple;
     }
 
   };
@@ -38,6 +48,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
   Polymer.PaperInkyFocusBehavior = [
     Polymer.IronButtonState,
     Polymer.IronControlState,
+    Polymer.PaperRippleBehavior,
     Polymer.PaperInkyFocusBehaviorImpl
   ];