Combined biometric settings implementation

There will be multiple biometrics authentications existing at the same
time, so we added a new page for multiple biometrics to control
biometrics settings.

Bug: 183449119
Test: manual test
Change-Id: I359082caf771e07dfd5b24973cb8a3cf372c1b30

src/com/android/settings/biometrics/face/FaceSettingsAppPreferenceController.java

@@ -78,6 +78,11 @@ public class FaceSettingsAppPreferenceController extends FaceSettingsPreferenceC
 
     @Override
     public int getAvailabilityStatus() {
+        // When the device supports multiple biometrics auth, this preference will be hidden.
+        if (Utils.isMultipleBiometricsSupported(mContext)) {
+            return UNSUPPORTED_ON_DEVICE;
+        }
+
         if(mFaceManager == null){
             return AVAILABLE_UNSEARCHABLE;
         }