src/vs/editor/standalone/browser/toggleHighContrast/toggleHighContrast.ts/ToggleHighContrast/constructor
class ToggleHighContrast:	constructor() {
		super({
			id: 'editor.action.toggleHighContrast',
			label: ToggleHighContrastNLS.toggleHighContrast,
			alias: 'Toggle High Contrast Theme',
			precondition: undefined
		});
		this._originalThemeName = null;
	}