Rerun reproduce to pick up a fix in a new version of paper-checkbox

third_party/polymer/v0_8/components/paper-checkbox/paper-checkbox.html

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@@ skipping 94 matching lines @@
        * Gets or sets the state, `true` is checked and `false` is unchecked.
        *
        * @attribute checked
        * @type boolean
        * @default false
        */
       checked: {
         type: Boolean,
         value: false,
         reflectToAttribute: true,
+        notify: true,
         observer: '_checkedChanged'
       },
 
       /**
        * If true, the user cannot interact with this element.
        *
        * @attribute disabled
        * @type boolean
        * @default false
        */
@@ skipping 29 matching lines @@
       }
     },
 
     _computeCheckmarkClass: function(checked) {
       if (!checked) {
         return 'hidden';
       }
     }
   })
 </script>