src/vs/workbench/services/themes/common/colorThemeData.ts/ColorThemeData/isThemeScope
class ColorThemeData:	public isThemeScope(key: string): boolean {
		return key.charAt(0) === THEME_SCOPE_OPEN_PAREN && key.charAt(key.length - 1) === THEME_SCOPE_CLOSE_PAREN;
	}