[GStreamer] Fix crash in event management

https://bugs.webkit.org/show_bug.cgi?id=294713

Reviewed by Philippe Normand.

We were leaking the ref just in the line above for OOB events which was causing the quirks to try to use a nullptr.

* Source/WebCore/platform/graphics/gstreamer/mse/WebKitMediaSourceGStreamer.cpp:
(webKitMediaSrcSendEvent):

Canonical link: https://commits.webkit.org/296413@main

Author: calvaris

Source/WebCore/platform/graphics/gstreamer/mse/WebKitMediaSourceGStreamer.cpp

@@ -851,7 +851,7 @@ static gboolean webKitMediaSrcSendEvent(GstElement* element, GstEvent* eventTran
                 wasEventHandledByAnyStream |= wasHandled;
             }
         } else
-            wasEventHandledByAnyStream = GST_ELEMENT_CLASS(webkit_media_src_parent_class)->send_event(element, event.leakRef());
+            wasEventHandledByAnyStream = GST_ELEMENT_CLASS(webkit_media_src_parent_class)->send_event(element, event.ref());
         auto rate = GStreamerQuirksManager::singleton().processWebKitMediaSrcCustomEvent(event, wasEventHandledByAnyStream, wasEventHandledByAllStreams);
         if (rate.has_value())
             source->priv->rate = rate.value();