Fix VerifyCredentialResponse parcelling code

There was an asymmetry between parcelling and unparcelling of
VerifyCredentialResponse that could lead to type confusion if
packed with other objects in a Parcel.

Test: none
Bug: 71714464
Change-Id: Icff68879e249422ccca49f2bb7db85c35b4cb353

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

@@ -95,6 +95,8 @@ public final class VerifyCredentialResponse implements Parcelable {
             if (mPayload != null) {
                 dest.writeInt(mPayload.length);
                 dest.writeByteArray(mPayload);
+            } else {
+                dest.writeInt(0);
             }
         }
     }