Don't show FP error canceled message

Test: manual test of SUW, error message doesn't show up when
      confirm credentials is complete

Change-Id: Ie0750629dcd5bb5d84df08c75e9c83384c299073
Fixes: 76400618

src/com/android/settings/fingerprint/FingerprintUiHelper.java

@@ -79,6 +79,10 @@ public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallba
 
     @Override
     public void onAuthenticationError(int errMsgId, CharSequence errString) {
+        if (errMsgId == FingerprintManager.FINGERPRINT_ERROR_CANCELED) {
+            // Only happens if we get preempted by another activity. Ignored.
+            return;
+        }
         showError(errString);
         setFingerprintIconVisibility(false);
     }