Fix cross-partition dependency handling (issue 26466)

pkg/analyzer/test/src/task/dart_work_manager_test.dart

Index: pkg/analyzer/test/src/task/dart_work_manager_test.dart
diff --git a/pkg/analyzer/test/src/task/dart_work_manager_test.dart b/pkg/analyzer/test/src/task/dart_work_manager_test.dart
index cb8fb464205d8a0764f216937c3807682c843385..da36f879b9f848511dccd4b3e71d8d7bd920ad8f 100644
--- a/pkg/analyzer/test/src/task/dart_work_manager_test.dart
+++ b/pkg/analyzer/test/src/task/dart_work_manager_test.dart
@@ -774,9 +774,16 @@ class _InternalAnalysisContextMock extends TypedMock
 
   Map<Source, ChangeNoticeImpl> _pendingNotices = <Source, ChangeNoticeImpl>{};
 
+  @override
+  final ReentrantSynchronousStream<InvalidatedResult> onResultInvalidated =
+      new ReentrantSynchronousStream<InvalidatedResult>();
+
   _InternalAnalysisContextMock() {
     privateAnalysisCachePartition = new UniversalCachePartition(this);
     analysisCache = new AnalysisCache([privateAnalysisCachePartition]);
+    analysisCache.onResultInvalidated.listen((InvalidatedResult event) {
+      onResultInvalidated.add(event);
+    });
   }
 
   @override