Hearts: Don't destroy the animation handler while running it

Author: https://github.com/gunnarbeutner
Commit: https://github.com/SerenityOS/serenity/commit/fab9b2f068c
Pull-request: https://github.com/SerenityOS/serenity/pull/7774

Userland/Games/Hearts/Game.cpp

@@ -270,8 +270,12 @@ void Game::timer_event(Core::TimerEvent&)
         if (m_animation_current_step >= m_animation_steps) {
             stop_timer();
             m_animation_playing = false;
-            if (m_animation_did_finish)
-                (*m_animation_did_finish)();
+            if (m_animation_did_finish) {
+                // The did_finish handler might end up destroying/replacing the handler
+                // so we have to save it first.
+                OwnPtr<Function<void()>> animation_did_finish = move(m_animation_did_finish);
+                (*animation_did_finish)();
+            }
         }
         m_animation_current_step++;
     }