src/vs/platform/windows/electron-main/windowImpl.ts/CodeWindow/ready
class CodeWindow:	ready(): Promise<ICodeWindow> {
		return new Promise<ICodeWindow>(resolve => {
			if (this.isReady) {
				return resolve(this);
			}

			// otherwise keep and call later when we are ready
			this.whenReadyCallbacks.push(resolve);
		});
	}