@TestOnly
  void assertNoReferenceKeptInTree(@NotNull Disposable disposable) {
    synchronized (getTreeLock()) {
      for (ObjectNode node : myObject2ParentNode.values()) {
        node.assertNoReferencesKept(disposable);
      }
    }
  }
@TestOnly
  void assertNoReferenceKeptInTree(@NotNull Disposable disposable)