Update bower.json for Polymer elements and add PRESUBMIT.py

third_party/polymer/v1_0/components-chromium/iron-pages/iron-pages-extracted.js

 
 
   Polymer({
 
     is: 'iron-pages',
 
     behaviors: [
       Polymer.IronResizableBehavior,
       Polymer.IronSelectableBehavior
     ],
 
+    properties: {
+
+      // as the selected page is the only one visible, activateEvent
+      // is both non-sensical and problematic; e.g. in cases where a user
+      // handler attempts to change the page and the activateEvent
+      // handler immediately changes it back
+      activateEvent: {
+        value: null
+      }
+
+    },
+
     observers: [
       '_selectedPageChanged(selected)'
     ],
 
     _selectedPageChanged: function(selected, old) {
       this.async(this.notifyResize);
     }
   });