src/vs/workbench/browser/layout.ts/Layout/getLayoutClasses
class Layout:	getLayoutClasses(): string[] {
		return coalesce([
			!this.isVisible(Parts.SIDEBAR_PART) ? WorkbenchLayoutClasses.SIDEBAR_HIDDEN : undefined,
			!this.isVisible(Parts.EDITOR_PART) ? WorkbenchLayoutClasses.EDITOR_HIDDEN : undefined,
			!this.isVisible(Parts.PANEL_PART) ? WorkbenchLayoutClasses.PANEL_HIDDEN : undefined,
			!this.isVisible(Parts.AUXILIARYBAR_PART) ? WorkbenchLayoutClasses.AUXILIARYBAR_HIDDEN : undefined,
			!this.isVisible(Parts.STATUSBAR_PART) ? WorkbenchLayoutClasses.STATUSBAR_HIDDEN : undefined,
			this.windowState.runtime.fullscreen ? WorkbenchLayoutClasses.FULLSCREEN : undefined
		]);
	}