Add entrance for B&R accessibility appearance related settings.
Flag: com.android.settings.flags.accessibility_appearance_settings_backup_enabled
Bug: 349941894
Bug: 328585994
Test: manual, need to open aconfig flag.
Change-Id: I9617da947201def01f2cfd7f20ce3d11d65f882d
Add entrance for B&R sound related settings.
Bug: 278975761
Test: manual, need to open aconfig flag.
Change-Id: I5396e9e260aea1ece3a507ee322c73308f69f94a
Add OnboardingFeatureProvider which will be used to B&R sound settings and
related tasks.
Bug: 289512753
Test: FakeFeatureFactory
Change-Id: I25e3b1f105ce0970cdf651400c153d8b4733029b