Schedule ChangeNotice results only after parse/resolve/errors.

pkg/analyzer/lib/src/task/dart_work_manager.dart

Index: pkg/analyzer/lib/src/task/dart_work_manager.dart
diff --git a/pkg/analyzer/lib/src/task/dart_work_manager.dart b/pkg/analyzer/lib/src/task/dart_work_manager.dart
index e006f86e5d0e11c8edf0f157b30d2d9f4c663881..dcb3f41a32773318937157c4c9036bd803fec8ab 100644
--- a/pkg/analyzer/lib/src/task/dart_work_manager.dart
+++ b/pkg/analyzer/lib/src/task/dart_work_manager.dart
@@ -282,7 +282,7 @@ class DartWorkManager implements WorkManager {
           context.getNotice(target).parsedDartUnit = value;
           shouldSetErrors = true;
         }
-        if (_isErrorResult(descriptor)) {
+        if (descriptor == DART_ERRORS) {
           shouldSetErrors = true;
         }
       });
@@ -299,9 +299,6 @@ class DartWorkManager implements WorkManager {
           context.getNotice(source).resolvedDartUnit = value;
           shouldSetErrors = true;
         }
-        if (_isErrorResult(descriptor)) {
-          shouldSetErrors = true;
-        }
       });
       if (shouldSetErrors) {
         AnalysisErrorInfo info = getErrors(source);
@@ -338,9 +335,4 @@ class DartWorkManager implements WorkManager {
   static bool _isDartSource(AnalysisTarget target) {
     return target is Source && AnalysisEngine.isDartFileName(target.fullName);
   }
-
-  static bool _isErrorResult(ResultDescriptor descriptor) {
-    return _SOURCE_ERRORS.contains(descriptor) ||
-        _UNIT_ERRORS.contains(descriptor);
-  }
 }