Don't set _destroyed

Author: Jelte Lagendijk

src/ChartJS/widgets/Core.js

@@ -75,7 +75,6 @@ define([
         _addedToBody: false,
 
         _tooltipNode: null,
-        _destroyed: false,
 
         startup: function () {
             logger.debug(this.id + ".startup");
@@ -259,8 +258,6 @@ define([
         uninitialize: function () {
             logger.debug(this.id + ".uninitialize");
 
-            this._destroyed = true;
-
             //console.log(this._data);
             if (this._handle !== null) {
                 this.unsubscribe(this._handle);