The registration after a login: the app always registers on a session start
(register_push_token_on_session_start), with session_change once the
install has registered before and with no trigger on its first registration.
A device restored from an earlier release that registered a caller's token
(MobileDeviceState.pushToken, before the device registered by itself)
registered before, though that release kept no lastPushRegistration.
The registration after a login: the app always registers on a session start (
register_push_token_on_session_start), withsession_changeonce the install has registered before and with no trigger on its first registration. A device restored from an earlier release that registered a caller's token (MobileDeviceState.pushToken, before the device registered by itself) registered before, though that release kept nolastPushRegistration.