Remove old #import, #source, and #library syntax from tests/standalone.

tests/standalone/package/invalid_uri_test.dart

Index: tests/standalone/package/invalid_uri_test.dart
diff --git a/tests/standalone/package/invalid_uri_test.dart b/tests/standalone/package/invalid_uri_test.dart
index 766dc7690236d0cff3cec76ae9521c2352793cf9..7015343e939a4ea9d4a59faded06e29e1b952184 100644
--- a/tests/standalone/package/invalid_uri_test.dart
+++ b/tests/standalone/package/invalid_uri_test.dart
@@ -2,9 +2,9 @@
 // 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('invalid_uri_test');
+library invalid_uri_test;
 
-#import('package://lib1.dart'); // Should not contain "//".
+import 'package://lib1.dart'; // Should not contain "//".
 
 void main() {
 }