Fixed enhanced for loop.

It was trying to interact through null, which could throw an exception. Example:

01-18 18:28:12.609   862  2038 W Binder  : Binder call failed.
01-18 18:28:12.609   862  2038 W Binder  : java.lang.NullPointerException: Attempt to get length of null array
01-18 18:28:12.609   862  2038 W Binder  : 	at android.app.Notification$Action$Builder.build(Notification.java:1289)

Test: manual verification
Change-Id: I84fda80ebd12df7d90730b17fa77d4b9ce5f58d2

core/java/android/app/Notification.java

@@ -1285,7 +1285,7 @@ public class Notification implements Parcelable
                 ArrayList<RemoteInput> dataOnlyInputs = new ArrayList<>();
                 RemoteInput[] previousDataInputs =
                     (RemoteInput[]) mExtras.getParcelableArray(EXTRA_DATA_ONLY_INPUTS);
-                if (previousDataInputs == null) {
+                if (previousDataInputs != null) {
                     for (RemoteInput input : previousDataInputs) {
                         dataOnlyInputs.add(input);
                     }