Declare a WTF if setting an alarm fails

This doesn't crash, but does trigger incident reporting.

Also adjust the dumpsys output to be a bit more sensible, and to include
not only last-wakeup but also last-trigger breadcrumbs.

Bug: 65489393
Test: manual
Change-Id: Ifb11f673ad5242b0320092731c9d8311a29f1170