SingleValueListeners that have completed should remove themselves from the list

of registered listeners in the database.

PiperOrigin-RevId: 269678254

Author: amablue

database/src/desktop/database_desktop.cc

@@ -43,9 +43,13 @@ namespace internal {
 Mutex g_database_reference_constructor_mutex;  // NOLINT
 
 SingleValueListener::SingleValueListener(DatabaseInternal* database,
+                                         const QuerySpec& query_spec,
                                          ReferenceCountedFutureImpl* future,
                                          SafeFutureHandle<DataSnapshot> handle)
-    : database_(database), future_(future), handle_(handle) {}
+    : database_(database),
+      query_spec_(query_spec),
+      future_(future),
+      handle_(handle) {}
 
 SingleValueListener::~SingleValueListener() {
   database_->RemoveSingleValueListener(this);

database/src/desktop/database_desktop.h

@@ -48,16 +48,18 @@ typedef int64_t WriteId;
 
 class SingleValueListener : public ValueListener {
  public:
-  SingleValueListener(DatabaseInternal* database,
+  SingleValueListener(DatabaseInternal* database, const QuerySpec& query_spec,
                       ReferenceCountedFutureImpl* future,
                       SafeFutureHandle<DataSnapshot> handle);
   // Unregister ourselves from the database.
   ~SingleValueListener() override;
   void OnValueChanged(const DataSnapshot& snapshot) override;
   void OnCancelled(const Error& error_code, const char* error_message) override;
+  const QuerySpec& query_spec() { return query_spec_; }
 
  private:
   DatabaseInternal* database_;
+  QuerySpec query_spec_;
   ReferenceCountedFutureImpl* future_;
   SafeFutureHandle<DataSnapshot> handle_;
 };
@@ -148,6 +150,7 @@ class DatabaseInternal {
           return *listener_holder == listener;
         });
     if (iter != single_value_listeners_.end()) {
+      repo_.RemoveEventCallback(listener, listener->query_spec());
       delete *iter;
       single_value_listeners_.erase(iter);
     }

database/src/desktop/query_desktop.cc

@@ -156,7 +156,7 @@ Future<DataSnapshot> QueryInternal::GetValue() {
   // TODO(b/68878322): Refactor this code to be less brittle, possibly using the
   // CleanupNotifier or something like it.
   SingleValueListener* single_listener =
-      new SingleValueListener(database_, query_future(), handle);
+      new SingleValueListener(database_, query_spec_, query_future(), handle);
 
   // If the database goes away, we need to be able to reach into these blocks
   // and clear their single_listener pointer. We can't do that directly, but we