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

tests/standalone/io/file_error_test.dart

Index: tests/standalone/io/file_error_test.dart
diff --git a/tests/standalone/io/file_error_test.dart b/tests/standalone/io/file_error_test.dart
index 218879e1b1dd92bc129adfff63357866f7483622..4cda95af8c5aea1bcfc14683f46dbe45f137e85d 100644
--- a/tests/standalone/io/file_error_test.dart
+++ b/tests/standalone/io/file_error_test.dart
@@ -4,8 +4,8 @@
 //
 // Dart test program for testing error handling in file I/O.
 
-#import("dart:io");
-#import("dart:isolate");
+import "dart:io";
+import "dart:isolate";
 
 Directory tempDir() {
   return new Directory('').createTempSync();