Exceptions on events not calling server-side UnhandledException infrastructure

[rynowak]

Exceptions thrown as a result of an event handler or JS Interop call don't call the server-side UnhandledException handler. Circuits and the sync context have their own unhandled exception events, and they don't fire for JS interop.

Is this right? I suppose the idea is that the exception is handled by the JS side. One piece of this that we need to be careful about is the fact that our exceptions aren't all going through a single path. For instance we don't have any hooks in place to sanitize these exceptions in production.

[mkArtakMSFT]

Goal:

• exceptions from calls from events should be logged on the server
• exceptions from calls from JSInterop should be handled on the client