Send notificatinos after no-op changes.

pkg/analysis_server/test/analysis/update_content_test.dart

Index: pkg/analysis_server/test/analysis/update_content_test.dart
diff --git a/pkg/analysis_server/test/analysis/update_content_test.dart b/pkg/analysis_server/test/analysis/update_content_test.dart
index 1fbcaa3feada0f07d190534781f38e36b50aff7c..f4d5bca234e2d638635c5ed6f76691d98e73ca83 100644
--- a/pkg/analysis_server/test/analysis/update_content_test.dart
+++ b/pkg/analysis_server/test/analysis/update_content_test.dart
@@ -87,4 +87,43 @@ f() {}
       expect(filesErrors[barPath], isEmpty);
     });
   }
+
+  test_sendNoticesAfterNopChange() async {
+    createProject();
+    addTestFile('');
+    await server.onAnalysisComplete;
+    // add an overlay
+    server.updateContent('1', {
+      testFile: new AddContentOverlay('main() {} main() {}')
+    });
+    await server.onAnalysisComplete;
+    // clear errors and make a no-op change
+    filesErrors.clear();
+    server.updateContent('2', {
+      testFile: new ChangeContentOverlay([new SourceEdit(0, 4, 'main')])
+    });
+    await server.onAnalysisComplete;
+    // errors should have been resent
+    expect(filesErrors, isNotEmpty);
+  }
+
+  test_sendNoticesAfterNopChange_flushedUnit() async {
+    createProject();
+    addTestFile('');
+    await server.onAnalysisComplete;
+    // add an overlay
+    server.updateContent('1', {
+      testFile: new AddContentOverlay('main() {} main() {}')
+    });
+    await server.onAnalysisComplete;
+    // clear errors and make a no-op change
+    filesErrors.clear();
+    server.test_flushResolvedUnit(testFile);
+    server.updateContent('2', {
+      testFile: new ChangeContentOverlay([new SourceEdit(0, 4, 'main')])
+    });
+    await server.onAnalysisComplete;
+    // errors should have been resent
+    expect(filesErrors, isNotEmpty);
+  }
 }