Remove legacy syntax support for library import

tests/co19/test_config.dart

Index: tests/co19/test_config.dart
===================================================================
--- tests/co19/test_config.dart	(revision 20447)
+++ tests/co19/test_config.dart	(working copy)
@@ -2,10 +2,10 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-#library("co19_test_config");
+library co19_test_config;
 
-#import('dart:io');
-#import('../../tools/testing/dart/test_suite.dart');
+import 'dart:io';
+import '../../tools/testing/dart/test_suite.dart';
 
 class Co19TestSuite extends StandardTestSuite {
   RegExp _testRegExp = new RegExp(r"t[0-9]{2}.dart$");