message: Resize viewer tab contents when the viewer tab changes
diff: @@ -24,6 +24,7 @@ import * as VirtualScrollArea from "./VirtualScrollArea";
  import * as WebIpc from "./WebIpc";
  import { AcceptsConfigDatabase, ConfigDatabase } from "../Config";
  import { ExtensionManager } from "./extension/InternalTypes";
  +import { ResizeNotifier } from "extraterm-resize-notifier";
  type VirtualScrollable = VirtualScrollArea.VirtualScrollable;
  @@ -50,6 +51,7 @@ export class EtViewerTab extends ViewerElement implements AcceptsConfigDatabase,
  SupportsClipboardPaste.SupportsClipboardPaste, SupportsDialogStack.SupportsDialogStack {
  static TAG_NAME = "ET-VIEWER-TAB";
  + private static _resizeNotifier = new ResizeNotifier();
  private _log: Logger;
  private _virtualScrollArea: VirtualScrollArea.VirtualScrollArea = null;
  @@ -58,7 +60,6 @@ export class EtViewerTab extends ViewerElement implements AcceptsConfigDatabase,
  private _tag: string = null;
  private _configDatabase: ConfigDatabase = null;
  - private _resizePollHandle: Disposable = null;
  private _elementAttached = false;
  private _needsCompleteRefresh = true;
  private _fontSizeAdjustment = 0;
  @@ -118,6 +119,11 @@ export class EtViewerTab extends ViewerElement implements AcceptsConfigDatabase,
  this.updateThemeCss();
  this._setupResizeCanary();
  + const containerDiv = DomUtils.getShadowId(this, ID_CONTAINER);
  + EtViewerTab._resizeNotifier.observe(containerDiv, (target: Element, contentRect: DOMRectReadOnly) => {
  + this._processResize();
  + });
  +
  doLater(this._processResize.bind(this));
  }
  @@ -181,10 +187,6 @@ export class EtViewerTab extends ViewerElement implements AcceptsConfigDatabase,
  if (element !== null) {
  element.dispose();
  }
  - if (this._resizePollHandle !== null) {
  - this._resizePollHandle.dispose();
  - this._resizePollHandle = null;
  - }
  }
  setConfigDatabase(newConfigDatabase: ConfigDatabase): void {
  