Add Toggle Controllers to XML

Autobrightness preference controller was accidentally removed from
display_settings.xml. Given that no tests were broken and this would
be a disaster for phone buddy & inline actions, I have added another
test which keeps a list of valid controllers that should exist in xml.

When more inline controllers types are added, they will be included
in this test.

Fixes: 72564979
Test: robotests
Change-Id: I40fe18f9118af9cec1c201632742d2949ff64be5

tests/robotests/src/com/android/settings/slices/SliceBuilderUtilsTest.java

@@ -29,6 +29,7 @@ import android.net.Uri;
 import com.android.settings.R;
 import com.android.settings.TestConfig;
 import com.android.settings.core.BasePreferenceController;
+import com.android.settings.testutils.FakeToggleController;
 import com.android.settings.testutils.SettingsRobolectricTestRunner;
 
 import org.junit.Before;