Partially revert notification of package map computation

pkg/analysis_server/test/context_manager_test.dart

Index: pkg/analysis_server/test/context_manager_test.dart
diff --git a/pkg/analysis_server/test/context_manager_test.dart b/pkg/analysis_server/test/context_manager_test.dart
index b43e501d07d001e3972fdebb67257d695ed88c9c..2104998f4c7d2c28cf449473951ec784bebc9cf2 100644
--- a/pkg/analysis_server/test/context_manager_test.dart
+++ b/pkg/analysis_server/test/context_manager_test.dart
@@ -2427,6 +2427,11 @@ class TestContextManagerCallbacks extends ContextManagerCallbacks {
   }
 
   @override
+  void computingPackageMap(bool computing) {
+    // Do nothing.
+  }
+
+  @override
   void removeContext(Folder folder, List<String> flushedFiles) {
     String path = folder.path;
     expect(currentContextPaths, contains(path));