update elements and fix some bugs

lib/src/iron-behaviors/iron-button-state.html

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@@ skipping 107 matching lines @@
 
     // to emulate native checkbox, (de-)activations from a user interaction fire
     // 'change' events
     _userActivate: function(active) {
       if (this.active !== active) {
         this.active = active;
         this.fire('change');
       }
     },
 
-    _eventSourceIsPrimaryInput: function(event) {
-      event = event.detail.sourceEvent || event;
-
-      // Always true for non-mouse events....
-      if (!this._mouseEventRe.test(event.type)) {
-        return true;
-      }
-
-      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/buttons
-      if ('buttons' in event) {
-        return event.buttons === 1;
-      }
-
-      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/which
-      if (typeof event.which === 'number') {
-        return event.which < 2;
-      }
-
-      // http://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/button
-      return event.button < 1;
-    },
-
     _downHandler: function(event) {
-      if (!this._eventSourceIsPrimaryInput(event)) {
-        return;
-      }
-
       this._setPointerDown(true);
       this._setPressed(true);
       this._setReceivedFocusFromKeyboard(false);
     },
 
     _upHandler: function() {
       this._setPointerDown(false);
       this._setPressed(false);
     },
 
@@ skipping 59 matching lines @@
 
   };
 
   /** @polymerBehavior */
   Polymer.IronButtonState = [
     Polymer.IronA11yKeysBehavior,
     Polymer.IronButtonStateImpl
   ];
 
 </script>