Revert useless changes to handle notebook shell

Author: brichet

js/jupyterlab-slideshow/src/manager.ts

@@ -44,7 +44,6 @@ export class DeckManager implements IDeckManager {
   protected _designTools: DesignTools | null = null;
   protected _settings: Promise<ISettingRegistry.ISettings>;
   protected _labShell?: LabShell | null;
-  protected _notebookShell?: INotebookShell | null;
   protected _dockPanel: DockPanel | null = null;
   protected _shell: JupyterFrontEnd.IShell;
   protected _statusbar: StatusBar | null;
@@ -509,16 +508,15 @@ export class DeckManager implements IDeckManager {
   }
 
   protected get _shellActiveWidget(): Widget | null {
-    const { _labShell, _notebookShell, _dockPanel } = this;
+    const { _labShell, _shell, _dockPanel } = this;
     if (_labShell && _dockPanel) {
       if (_labShell.activeWidget) {
         return _labShell.activeWidget;
       }
       return getSelectedWidget(_dockPanel);
-    } else if (_notebookShell) {
-      return _notebookShell.currentWidget || null;
+    } else {
+      return (_shell as INotebookShell).currentWidget || null;
     }
-    return null;
   }
 
   protected async _onSettingsChanged() {
@@ -603,7 +601,6 @@ export namespace DeckManager {
   export interface IOptions {
     commands: CommandRegistry;
     labShell: ILabShell | null;
-    notebookShell: INotebookShell | null;
     shell: JupyterFrontEnd.IShell;
     translator: TranslationBundle;
     statusbar: StatusBar | null;

js/jupyterlab-slideshow/src/plugin.ts

@@ -1,5 +1,4 @@
 import { IFontManager } from '@deathbeds/jupyterlab-fonts';
-import { INotebookShell } from '@jupyter-notebook/application';
 import {
   JupyterFrontEnd,
   JupyterFrontEndPlugin,
@@ -33,7 +32,7 @@ import '../style/index.css';
 const plugin: JupyterFrontEndPlugin<IDeckManager> = {
   id: `${NS}:plugin`,
   requires: [ITranslator, ISettingRegistry, IFontManager],
-  optional: [ILabShell, INotebookShell, ILayoutRestorer, ICommandPalette, IStatusBar],
+  optional: [ILabShell, ILayoutRestorer, ICommandPalette, IStatusBar],
   provides: IDeckManager,
   autoStart: true,
   activate: (
@@ -42,7 +41,6 @@ const plugin: JupyterFrontEndPlugin<IDeckManager> = {
     settings: ISettingRegistry,
     fonts: IFontManager,
     labShell?: ILabShell,
-    notebookShell?: INotebookShell,
     restorer?: ILayoutRestorer,
     palette?: ICommandPalette,
     statusbar?: IStatusBar,
@@ -56,7 +54,6 @@ const plugin: JupyterFrontEndPlugin<IDeckManager> = {
       commands,
       shell,
       labShell: labShell || null,
-      notebookShell: notebookShell || null,
       translator: (translator || /* istanbul ignore next */ nullTranslator).load(NS),
       statusbar: theStatusBar,
       fonts,