commit 5e6777feed490a1d552902125218acf96b0dc9e0
author Aaron Zinman <aaron@azinman.com> Wed Jul 20 19:24:09 2016 -0700
committer Aaron Zinman <aaron@azinman.com> Wed Jul 20 19:24:09 2016 -0700
tree 834f6fc130780aeff18bf46cf63100a717ea7a7b
parent 23652a8648b38ff55a6573764bf6f6ac86f02336

ref: Prevent crashes when advertising >16 syncgroups

Currently two related crashes will occur should the user have more
than 16 syncgroups. The root of the cause is Serve() will start
advertising each syncgroup, and if the platform has BLE then
some will fail as the current BLE implementation can only support
16 total advertisements. If BLE advertisement fails, one crash was
a null dereference of the advertisement's stop().  Note CL #23804
fixed this type of crash in one place in the function there was
another where stop could be nil and dereferenced.

The other crash is a vlog.Fatal should advertising syncgroups fail. This
CL allows advertising to continue (only logging errors) should at least
one plugin work. That way BLE can work up to its max, but mDNS can
continue advertising all syncgroups.  This is one solve the >16 BLE
advertisements issue with BLE, filed as vanadium/issues#1404.

Closes vanadium/issues#1390, vanadium/issues#1403, vanadium/issues#1398

Change-Id: I07fee516a5246ad8ff72e1107158c16f33d68562