src/vs/workbench/api/browser/mainThreadWindow.ts/MainThreadWindow/constructor
class MainThreadWindow:	constructor(
		extHostContext: IExtHostContext,
		@IHostService private readonly hostService: IHostService,
		@IOpenerService private readonly openerService: IOpenerService,
	) {
		this.proxy = extHostContext.getProxy(ExtHostContext.ExtHostWindow);

		Event.latch(hostService.onDidChangeFocus)
			(this.proxy.$onDidChangeWindowFocus, this.proxy, this.disposables);
	}