Now that we support email aliases, we have to be careful when going from
an email address to a domain that we assume we can use to get a Realm
object for. When we care about the Realm's domain, we want to follow
any RealmAliases that exist for a certain domain.
When we just care about the original email address domain itself,
for comparison or other purposes, use split_email_from_domain
This removes the ambiguity of having to decide when to use
email_to_domain + RealmAlias or just email_to_domain
(imported from commit 0e199495502d946ce2e1aae56263e7e8665be4ed)
This needs to be deployed to both staging and prod at the same
off-peak time (and the schema migration run).
At the time it is deployed, we need to make a few changes directly in
the database:
(1) UPDATE django_content_type set app_label='zerver' where app_label='zephyr';
(2) UPDATE south_migrationhistory set app_name='zerver' where app_name='zephyr';
(imported from commit eb3fd719571740189514ef0b884738cb30df1320)