Not allowing empty fingerprint names anymore

Bug: 22497103
Change-Id: I638b1db5b614f5ea9bf8e3566bf4619a3249d391
diff --git a/services/core/java/com/android/server/fingerprint/FingerprintUtils.java b/services/core/java/com/android/server/fingerprint/FingerprintUtils.java
index d274412..49dc8e4 100644
--- a/services/core/java/com/android/server/fingerprint/FingerprintUtils.java
+++ b/services/core/java/com/android/server/fingerprint/FingerprintUtils.java
@@ -19,6 +19,7 @@
 import android.content.Context;
 import android.hardware.fingerprint.Fingerprint;
 import android.os.Vibrator;
+import android.text.TextUtils;
 import android.util.SparseArray;
 
 import com.android.internal.annotations.GuardedBy;
@@ -64,6 +65,10 @@
     }
 
     public void renameFingerprintForUser(Context ctx, int fingerId, int userId, CharSequence name) {
+        if (TextUtils.isEmpty(name)) {
+            // Don't do the rename if it's empty
+            return;
+        }
         getStateForUser(ctx, userId).renameFingerprint(fingerId, name);
     }