Don't send a refactoring feedback in case of a fatal initial problem.

pkg/analysis_server/lib/src/edit/edit_domain.dart

Index: pkg/analysis_server/lib/src/edit/edit_domain.dart
diff --git a/pkg/analysis_server/lib/src/edit/edit_domain.dart b/pkg/analysis_server/lib/src/edit/edit_domain.dart
index ad085755c79d5d39066baa512739524cb92780c5..eb4bbf4168048e48f85e8edb1dc7d178282fc1c9 100644
--- a/pkg/analysis_server/lib/src/edit/edit_domain.dart
+++ b/pkg/analysis_server/lib/src/edit/edit_domain.dart
@@ -254,6 +254,7 @@ class _RefactoringManager {
     var params = new EditGetRefactoringParams.fromRequest(request);
     _init(params.kind, params.file, params.offset, params.length).then((_) {
       if (initStatus.hasFatalError) {
+        feedback = null;
         return _sendResultResponse();
       }
       // set options
@@ -453,9 +454,7 @@ class _RefactoringManager {
   }
 
   void _sendResultResponse() {
-    if (feedback != null) {
-      result.feedback = feedback;
-    }
+    result.feedback = feedback;
     // set problems
     result.initialProblems = initStatus.problems;
     result.optionsProblems = optionsStatus.problems;