Fork SettingsDrawerActivity in Settings.

Settings app uses fragment classes from android framework,
which is deprecated as of P.
We need to switch to use fragment and associated classes to androidx.

Because Settings didn't support drawer feature since Android O,
we rename SettingsDrawerActivity to SettingsBaseActivity.

Before we migrate to fragment of androix,
we need to let SettingsBaseActivity extend FragmentActivity.

Test: make RunSettingsRoboTests
Bug: 110259478
Change-Id: Ifbf53f75f042da1618da16cf7837b70d298a9a14