When a transaction completes, the NoopListener should be removed so that it

does not respond to further changes to the database. If it were not removed and
the listener is deleted then this would result in a crash on the next write to
the database.

PiperOrigin-RevId: 251932053

Author: amablue

database/src/desktop/core/repo.cc

@@ -512,9 +512,10 @@ void Repo::StartTransaction(const Path& path,
       new DatabaseReferenceInternal(database_, path);
   DatabaseReference watch_ref(ref_impl);
   UniquePtr<NoopListener> listener = MakeUnique<NoopListener>();
+  NoopListener* listener_ptr = listener.get();
   QuerySpec query_spec(path);
-  AddEventCallback(MakeUnique<ValueEventRegistration>(database_, listener.get(),
-                                                      query_spec));
+  AddEventCallback(
+      MakeUnique<ValueEventRegistration>(database_, listener_ptr, query_spec));
 
   TransactionDataPtr transaction_data = MakeShared<TransactionData>(
       handle, api, query_spec.path, transaction_function, context,
@@ -535,6 +536,9 @@ void Repo::StartTransaction(const Path& path,
     transaction_data->status = TransactionData::kStatusNeedsAbort;
     transaction_data->ref_future->Complete(transaction_data->future_handle,
                                            kErrorWriteCanceled);
+    // If there was an error, the listener must be removed to prevent calls to
+    // it in case the listener is destroyed.
+    RemoveEventCallback(listener_ptr, query_spec);
   } else {
     // Mark as run and add to our queue.
     transaction_data->status = TransactionData::kStatusRun;