Return error when importmulti called with invalid address.

Lack of error checking noticed by Alex Morcos <morcos@chaincode.com>

qa/rpc-tests/importmulti.py

@@ -59,6 +59,16 @@ class ImportMultiTest (BitcoinTestFramework):
         assert_equal(address_assert['iswatchonly'], True)
         assert_equal(address_assert['ismine'], False)
 
+        print("Should not import an invalid address")
+        result = self.nodes[1].importmulti([{
+            "scriptPubKey": {
+                "address": "not valid address",
+            },
+            "timestamp": "now",
+        }])
+        assert_equal(result[0]['success'], False)
+        assert_equal(result[0]['error']['code'], -5)
+        assert_equal(result[0]['error']['message'], 'Invalid address')
 
         # ScriptPubKey + internal
         print("Should import a scriptPubKey with internal flag")

src/wallet/rpcdump.cpp

@@ -671,6 +671,9 @@ UniValue processImport(const UniValue& data) {
 
         if (!isScript) {
             address = CBitcoinAddress(output);
+            if (!address.IsValid()) {
+                throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid address");
+            }
             script = GetScriptForDestination(address.Get());
         } else {
             if (!IsHex(output)) {