src/vs/workbench/browser/layout.ts/Layout/isVisible
class Layout:	isVisible(part: Parts): boolean {
		if (this.initialized) {
			switch (part) {
				case Parts.TITLEBAR_PART:
					return this.workbenchGrid.isViewVisible(this.titleBarPartView);
				case Parts.SIDEBAR_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.SIDEBAR_HIDDEN);
				case Parts.PANEL_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.PANEL_HIDDEN);
				case Parts.AUXILIARYBAR_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.AUXILIARYBAR_HIDDEN);
				case Parts.STATUSBAR_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.STATUSBAR_HIDDEN);
				case Parts.ACTIVITYBAR_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.ACTIVITYBAR_HIDDEN);
				case Parts.EDITOR_PART:
					return !this.stateModel.getRuntimeValue(LayoutStateKeys.EDITOR_HIDDEN);
				case Parts.BANNER_PART:
					return this.workbenchGrid.isViewVisible(this.bannerPartView);
				default:
					return false; // any other part cannot be hidden
			}
		}

		switch (part) {
			case Parts.TITLEBAR_PART:
				return this.shouldShowTitleBar();
			case Parts.SIDEBAR_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.SIDEBAR_HIDDEN);
			case Parts.PANEL_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.PANEL_HIDDEN);
			case Parts.AUXILIARYBAR_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.AUXILIARYBAR_HIDDEN);
			case Parts.STATUSBAR_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.STATUSBAR_HIDDEN);
			case Parts.ACTIVITYBAR_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.ACTIVITYBAR_HIDDEN);
			case Parts.EDITOR_PART:
				return !this.stateModel.getRuntimeValue(LayoutStateKeys.EDITOR_HIDDEN);
			default:
				return false; // any other part cannot be hidden
		}
	}