notificationDaemon: Work around JS interpreter bug

notificationDaemon: Work around JS interpreter bug

The "id" variable was being sporadically reset to null, and as far as
Florian and I could determine, this is actually a Spidermonkey bug.

The issue has something to do with:

1) use of "let" for the variable
2) Nesting a dynamic closure inside of a for() loop

Work around it here for now - I tried to create a minimized test case
to hand to the Spidermonkey developers, but failed.  A big part of
the problem is it's only sporadically reproducible.