Fix jank: Don't write lockout deadline if not needed

In the longterm, we should move these synchronous writes
off the main thread, but in the short term, avoiding an unnecessary
write is good enough for the main case.

Bug: 24471234
Change-Id: Id996ff29e61410cd077760a06d7868a413ae88da

core/java/com/android/internal/widget/LockPatternUtils.java

@@ -1074,7 +1074,7 @@ public class LockPatternUtils {
         long deadline = getLong(LOCKOUT_ATTEMPT_DEADLINE, 0L, userId);
         final long timeoutMs = getLong(LOCKOUT_ATTEMPT_TIMEOUT_MS, 0L, userId);
         final long now = SystemClock.elapsedRealtime();
-        if (deadline < now) {
+        if (deadline < now && deadline != 0) {
             // timeout expired
             setLong(LOCKOUT_ATTEMPT_DEADLINE, 0, userId);
             setLong(LOCKOUT_ATTEMPT_TIMEOUT_MS, 0, userId);