message: Fix a regression bug which broke the drag and drop for tabs.
diff: @@ -7,40 +7,22 @@ import * as DomUtils from '../DomUtils';
  import * as Util from './Util';
  import {Logger, getLogger} from '../../logging/Logger';
  import log from '../../logging/LogDecorator';
  +import { WebComponent } from 'extraterm-web-component-decorators';
  /**
  * Holds the contents of one tab inside a TabWidget tag.
  */
  +@WebComponent({tag: "et-tab"})
  export class Tab extends HTMLElement {
  static TAG_NAME = "ET-TAB";
  - //-----------------------------------------------------------------------
  - // WARNING: Fields like this will not be initialised automatically. See _initProperties().
  private _log: Logger;
  -
  private _mutationObserver: MutationObserver;
  - private _initProperties(): void {
  - this._mutationObserver = null;
  - this._log = getLogger(Tab.TAG_NAME, this);
  - }
  -
  - //-----------------------------------------------------------------------
  - //
  - // #
  - // # # ###### ###### #### # # #### # ######
  - // # # # # # # # # # # # #
  - // # # ##### ##### # # # # #####
  - // # # # # # # # # #
  - // # # # # # # # # # # #
  - // ####### # # ###### #### # #### ###### ######
  - //
  - //-----------------------------------------------------------------------
  -
  constructor() {
  super();
  - this._initProperties();
  + this._log = getLogger(Tab.TAG_NAME, this);
  this._mutationObserver = new MutationObserver( (mutations) => {
  this._applyDraggable();
  