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
(cherry picked from commit 54813e988884f0d604d5358569f10feda8622f46)
diff --git a/core/java/com/android/internal/widget/VerifyCredentialResponse.java b/core/java/com/android/internal/widget/VerifyCredentialResponse.java
index ad6020c..7d1c706 100644
--- a/core/java/com/android/internal/widget/VerifyCredentialResponse.java
+++ b/core/java/com/android/internal/widget/VerifyCredentialResponse.java
@@ -98,6 +98,8 @@
             if (mPayload != null) {
                 dest.writeInt(mPayload.length);
                 dest.writeByteArray(mPayload);
+            } else {
+                dest.writeInt(0);
             }
         }
     }