src/vs/editor/common/cursor/cursorTypeOperations.ts/TypeOperations/unshiftIndent
class TypeOperations:	public static unshiftIndent(config: CursorConfiguration, indentation: string, count?: number): string {
		count = count || 1;
		return ShiftCommand.unshiftIndent(indentation, indentation.length + count, config.tabSize, config.indentSize, config.insertSpaces);
	}