[B&R] ignore backup system app or default app optimization modes

Avoid backup system app or default app optimization modes, since all of
them are using the MODE_UNRESTRICTED in default, and the system or
default apps may be different in the different devices.

BYPASS_INCLUSIVE_LANGUAGE_REASON=legacy method name

Test command for backup manager:
adb shell bmgr backupnow com.android.settings
adb shell dumpsys backup | grep Current

Bug: 192523697
Test: make SettingsRoboTests
Change-Id: I0862ee31fcfa3bece15c2d4fdef5b0ea70235967