Upgrade to 1.0 and switch clients to dom-repeat where needed.

third_party/polymer/v0_8/components/paper-behaviors/paper-radio-button-behavior.html

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 @license
 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 -->
 
 <link rel="import" href="../polymer/polymer.html">
 <link rel="import" href="../iron-behaviors/iron-button-state.html">
 
 <script>
 
+  /** @polymerBehavior */
   Polymer.PaperRadioButtonInk = {
 
     observers: [
-      `_focusedChanged(focused)`
+      '_focusedChanged(receivedFocusFromKeyboard)'
     ],
 
-    _focusedChanged: function(focused) {
-      if (!this.$.ink)
+    _focusedChanged: function(receivedFocusFromKeyboard) {
+      if (!this.$.ink) {
         return;
+      }
 
-      if (focused) {
-        var rect = this.$.ink.getBoundingClientRect();
-        this.$.ink.mousedownAction();
-      } else {
-        this.$.ink.mouseupAction();
-      }
+      this.$.ink.holdDown = receivedFocusFromKeyboard;
     }
 
   };
 
+  /** @polymerBehavior */
   Polymer.PaperRadioButtonBehavior = [
+    Polymer.IronButtonState,
     Polymer.IronControlState,
-    Polymer.IronButtonState,
     Polymer.PaperRadioButtonInk
   ];
 
 </script>