Renderer.DispatchEventAsync throws null reference exception if event handler throws synchronously #11847
Description
From #11791
If an event handler throws synchronously, there's a bug in Renderer.DispatchEventAsync. The task variable is left with a null value, which then throws a nullref exception in GetErrorHandledTask.
The correct behavior would be to still treat this as a circuit-terminating exception, but report the real exception and don't have the nullref. Currently I believe it logs both the real exception and the subsequent nullref.