src/vs/workbench/browser/parts/panel/panelActions.ts/TogglePanelAction/constructor
class TogglePanelAction:	constructor(
		id: string,
		name: string,
		@IWorkbenchLayoutService private readonly layoutService: IWorkbenchLayoutService
	) {
		super(id, name, layoutService.isVisible(Parts.PANEL_PART) ? 'panel expanded' : 'panel');
	}