Get computeError working

pkg/analyzer/lib/src/plugin/engine_plugin.dart

Index: pkg/analyzer/lib/src/plugin/engine_plugin.dart
diff --git a/pkg/analyzer/lib/src/plugin/engine_plugin.dart b/pkg/analyzer/lib/src/plugin/engine_plugin.dart
index 9cd0577ea4f64fb0999e18bc91b39dce7e960fc5..42b41b1cc8fe6eeb40a92e19d84fb6e08234b06a 100644
--- a/pkg/analyzer/lib/src/plugin/engine_plugin.dart
+++ b/pkg/analyzer/lib/src/plugin/engine_plugin.dart
@@ -72,9 +72,12 @@ class EnginePlugin implements Plugin {
     registerExtension(taskId, BuildPublicNamespaceTask.DESCRIPTOR);
     registerExtension(taskId, BuildSourceClosuresTask.DESCRIPTOR);
     registerExtension(taskId, BuildTypeProviderTask.DESCRIPTOR);
+    registerExtension(taskId, ContainingLibrariesTask.DESCRIPTOR);
+    registerExtension(taskId, DartErrorsTask.DESCRIPTOR);
     registerExtension(taskId, GatherUsedImportedElementsTask.DESCRIPTOR);
     registerExtension(taskId, GatherUsedLocalElementsTask.DESCRIPTOR);
     registerExtension(taskId, GenerateHintsTask.DESCRIPTOR);
+    registerExtension(taskId, LibraryUnitErrorsTask.DESCRIPTOR);
     registerExtension(taskId, ParseDartTask.DESCRIPTOR);
     registerExtension(taskId, ResolveLibraryTypeNamesTask.DESCRIPTOR);
     registerExtension(taskId, ResolveReferencesTask.DESCRIPTOR);