Prevent finishing early on single sensor devices.

Fixes regression from commit c358adad56.

Fix: 192420564
Fix: 188847063

Test: manual enroll face & fingerprint via setup wizard (on fp, face, & fp+face device variants)
Change-Id: If7027e4d0ddf9d73daf91f174f237e4eb1621ea7

src/com/android/settings/biometrics/BiometricEnrollActivity.java

@@ -242,6 +242,7 @@ public class BiometricEnrollActivity extends InstrumentedActivity {
         // This will need to be updated if the device has sensors other than BIOMETRIC_STRONG
         if (!setupWizard && authenticators == BiometricManager.Authenticators.DEVICE_CREDENTIAL) {
             launchCredentialOnlyEnroll();
+            finish();
         } else if (canUseFace && canUseFingerprint) {
             if (mParentalOptionsRequired && mGkPwHandle != null) {
                 launchFaceAndFingerprintEnroll();
@@ -405,22 +406,6 @@ public class BiometricEnrollActivity extends InstrumentedActivity {
         super.onApplyThemeResource(theme, newResid, first);
     }
 
-    @Override
-    protected void onStop() {
-        super.onStop();
-
-        if (mConfirmingCredentials
-                || mParentalOptionsRequired
-                || mMultiBiometricEnrollHelper != null) {
-            return;
-        }
-
-        if (!isChangingConfigurations()) {
-            Log.d(TAG, "Finishing in onStop");
-            finish();
-        }
-    }
-
     private void setOrConfirmCredentialsNow() {
         if (!mConfirmingCredentials) {
             mConfirmingCredentials = true;