Use DB_MASTER in loadFromDatabase()/getSectionsForSave()

The sections are then sent via checkInput() to markForTranslation()
which will propagate them in various tables, jobs and caches.
It seems much better to be sure that they're actually what we're
looking for, i.e. the latest version.

Change-Id: Iaeae257b7ebcfd901019c6c247284d29eef20bd4
Merge "Use DB_MASTER in loadFromDatabase()/getSectionsForSave()"