Add logging to see why attachments fail to load

Now, if we ever insert or update an attachment to have
a blank location, we'll log a warning with stack trace.
Also, logging from ADS now uses the same log tag as everything
else, so we'll be able to see it without needing to turn
on some funny log tag.

Change-Id: Ic566cd87e8893128d074b897d7594a01ae12bc8c
2 files changed