Add destroy to Parser module

src/editor/model/Editor.js

@@ -765,7 +765,8 @@ export default Backbone.Model.extend({
       Commands,
       DeviceManager,
       I18n,
-      Modal
+      Modal,
+      Parser
     } = this.attributes;
     this.stopDefault();
     DomComponents.destroy();
@@ -783,6 +784,7 @@ export default Backbone.Model.extend({
     DeviceManager.destroy();
     I18n.destroy();
     Modal.destroy();
+    Parser.destroy();
     this.view.remove();
     this.stopListening();
     this.clear({ silent: true });

src/parser/index.js

@@ -72,6 +72,11 @@ export default () => {
      */
     parseCss(str) {
       return pCss.parse(str);
+    },
+
+    destroy() {
+      [conf, pHtml, pCss].forEach(i => (i = {}));
+      ['em', 'parserCss', 'parserHtml'].forEach(i => (this[i] = {}));
     }
   };
 };