Creates a flag for auto-rotate with face detection

The flag is enabled by default. And will be disabled on foldable
devices.

Test: locally
Bug: 236249360

Change-Id: I8c90533f6011531a4f00af5f2514579638604067

tests/robotests/src/com/android/settings/display/SmartAutoRotatePreferenceControllerTest.java

@@ -80,6 +80,9 @@ public class SmartAutoRotatePreferenceControllerTest {
         when(mContext.getResources()).thenReturn(mResources);
         when(mContext.getContentResolver()).thenReturn(mContentResolver);
 
+        when(mResources.getBoolean(R.bool.config_auto_rotate_face_detection_available)).thenReturn(
+                true);
+
         doReturn(PACKAGE_NAME).when(mPackageManager).getRotationResolverPackageName();
         doReturn(PackageManager.PERMISSION_GRANTED).when(mPackageManager).checkPermission(
                 Manifest.permission.CAMERA, PACKAGE_NAME);