Fix the failing test!

src/wallet/wallet.h

@@ -222,6 +222,7 @@ public:
     inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
         READWRITE(address);
         READWRITE(nullifier);
+        READWRITE(witnesses);
     }
 
     friend bool operator<(const CNoteData& a, const CNoteData& b) {

src/zcash/IncrementalMerkleTree.hpp

@@ -131,6 +131,9 @@ class IncrementalWitness {
 friend class IncrementalMerkleTree<Depth, Hash>;
 
 public:
+    // Required for Unserialize()
+    IncrementalWitness() {}
+
     MerklePath path() const {
         return tree.path(partial_path());
     }