Avoid aborting sms kill switch cleanup on unexpected exception

There was a report of a kill switch not working as intended, which seems
to be related to an unexpected exception happening during the cleanup:
https://paste.googleplex.com/6587646319001600

It's difficult to pinpoint the exact root cause, as it's only reproducible
on a userdebug device that is used as a personal one, so for now we should
at least take a precaution to ensure any such failure's effect is localized
to the problematic package/permission pair instead of bringing down the entire
process.

Bug: 124789865
Test: presubmit
Change-Id: I9f31954623fc22ac363d6fb8b1ceea3f6407214c