Closes #3560. Update Sapling note data correctly when importing a key.

qa/rpc-tests/wallet_sapling.py

@@ -136,5 +136,13 @@ class WalletSaplingTest(BitcoinTestFramework):
         assert('outCiphertext' in shieldedOutput)
         assert('proof' in shieldedOutput)
 
+        # Verify importing a spending key will update the nullifiers and witnesses correctly
+        sk0 = self.nodes[0].z_exportkey(saplingAddr0)
+        self.nodes[2].z_importkey(sk0, "yes")
+        assert_equal(self.nodes[2].z_getbalance(saplingAddr0), Decimal('10'))
+        sk1 = self.nodes[1].z_exportkey(saplingAddr1)
+        self.nodes[2].z_importkey(sk1, "yes")
+        assert_equal(self.nodes[2].z_getbalance(saplingAddr1), Decimal('5'))
+
 if __name__ == '__main__':
     WalletSaplingTest().main()

src/wallet/wallet.cpp

@@ -2367,7 +2367,7 @@ int CWallet::ScanForWalletTransactions(CBlockIndex* pindexStart, bool fUpdate)
                 }
             }
             // Increment note witness caches
-            IncrementNoteWitnesses(pindex, &block, sproutTree, saplingTree);
+            ChainTip(pindex, &block, sproutTree, saplingTree, true);
 
             pindex = chainActive.Next(pindex);
             if (GetTime() >= nNow + 60) {