[winedbg] Don't ever pass a NONCONTINUABLE exception

[Glenn Wurster]

> >Not really, if the app handles the exception there's no reason it
> >would fail.
> 
> And that's just what safedisc does so please don't change it because it 
> appears to work and enough things it needs are broken already.

I'm not looking to change exception handling at the application level,
just trying to make the debugger work better.  Again,
EXCEPTION_NONCONTINUABLE was the wrong flag to check, EH_STACK_INVALID
is what the revised patch checks, because exceptions with this flag
will never make it to the application at all anyway.

Glenn.