Unify Counter generation from notifications

This will make sure we don't lose any metadata information from
notifications into the Counter/samples we publish.

This is part of fixing bug #1187833 and bug #1187843

Change-Id: I315581907be1dcec33f43a5d5fd7b7876a7889f6
Signed-off-by: Julien Danjou <julien@danjou.info>
Merge "Unify Counter generation from notifications"