Fix the test on Windows.

pkg/analyzer/test/generated/compile_time_error_code_test.dart

Index: pkg/analyzer/test/generated/compile_time_error_code_test.dart
diff --git a/pkg/analyzer/test/generated/compile_time_error_code_test.dart b/pkg/analyzer/test/generated/compile_time_error_code_test.dart
index 962f4b4b4ee6e1624f39f32a5e52c5f9705fcd49..b3259a2aa92f56e33f66aa389cb67f81739e966d 100644
--- a/pkg/analyzer/test/generated/compile_time_error_code_test.dart
+++ b/pkg/analyzer/test/generated/compile_time_error_code_test.dart
@@ -6157,7 +6157,7 @@ main() {
     assertErrors(test, [HintCode.UNUSED_IMPORT]);
 
     // Remove the overlay in the same way as AnalysisServer.
-    resourceProvider.deleteFile('/target.dart');
+    resourceProvider.deleteFile(resourceProvider.convertPath('/target.dart'));
     analysisContext2.setContents(target, null);
     ChangeSet changeSet = new ChangeSet()..removedSource(target);
     analysisContext2.applyChanges(changeSet);