Handle fp enrollment errors more gracefully

- When finger can't be analyzed for enrollment
(FINGERPRINT_ERROR_UNABLE_TO_PROCESS), tell the user
to try again or use a different finger.
- When timeout is reached (FINGERPRINT_ERROR_TIMEOUT),
stop enrollment and ask the user to try again.

Fixes bug 23546104
Fixes bug 22708384

Change-Id: I879874b53dd0d928093fab1c92d0d4d68d73be28

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

@@ -80,6 +80,9 @@ public class FingerprintEnrollFindSensor extends FingerprintEnrollBase {
             } else if (resultCode == RESULT_SKIP) {
                 setResult(RESULT_SKIP);
                 finish();
+            } else if (resultCode == RESULT_TIMEOUT) {
+                setResult(RESULT_TIMEOUT);
+                finish();
             } else {
                 FingerprintManager fpm = getSystemService(FingerprintManager.class);
                 int enrolled = fpm.getEnrolledFingerprints().size();