src/vs/workbench/browser/layout.ts/Layout/toggleMenuBar
class Layout:	toggleMenuBar(): void {
		let currentVisibilityValue = getMenuBarVisibility(this.configurationService);
		if (typeof currentVisibilityValue !== 'string') {
			currentVisibilityValue = 'classic';
		}

		let newVisibilityValue: string;
		if (currentVisibilityValue === 'visible' || currentVisibilityValue === 'classic') {
			newVisibilityValue = getTitleBarStyle(this.configurationService) === 'native' ? 'toggle' : 'compact';
		} else {
			newVisibilityValue = 'classic';
		}

		this.configurationService.updateValue(Storage.MENU_VISIBILITY, newVisibilityValue);
	}