Prevent RPC 'move' from deadlocking

It seemed to create two CWalletDB objects that both grab the
database lock.

src/rpcwallet.cpp

@@ -573,7 +573,7 @@ Value movecmd(const Array& params, bool fHelp)
 
     // Debit
     CAccountingEntry debit;
-    debit.nOrderPos = pwalletMain->IncOrderPosNext();
+    debit.nOrderPos = pwalletMain->IncOrderPosNext(&walletdb);
     debit.strAccount = strFrom;
     debit.nCreditDebit = -nAmount;
     debit.nTime = nNow;
@@ -583,7 +583,7 @@ Value movecmd(const Array& params, bool fHelp)
 
     // Credit
     CAccountingEntry credit;
-    credit.nOrderPos = pwalletMain->IncOrderPosNext();
+    credit.nOrderPos = pwalletMain->IncOrderPosNext(&walletdb);
     credit.strAccount = strTo;
     credit.nCreditDebit = nAmount;
     credit.nTime = nNow;

src/wallet.cpp

@@ -291,10 +291,14 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
     return true;
 }
 
-int64 CWallet::IncOrderPosNext()
+int64 CWallet::IncOrderPosNext(CWalletDB *pwalletdb)
 {
-    int64 nRet = nOrderPosNext;
+    int64 nRet = nOrderPosNext++;
-    CWalletDB(strWalletFile).WriteOrderPosNext(++nOrderPosNext);
+    if (pwalletdb) {
+        pwalletdb->WriteOrderPosNext(nOrderPosNext);
+    } else {
+        CWalletDB(strWalletFile).WriteOrderPosNext(nOrderPosNext);
+    }
     return nRet;
 }
 

src/wallet.h

@@ -149,7 +149,7 @@ public:
     /** Increment the next transaction order id
         @return next transaction order id
      */
-    int64 IncOrderPosNext();
+    int64 IncOrderPosNext(CWalletDB *pwalletdb = NULL);
 
     typedef std::pair<CWalletTx*, CAccountingEntry*> TxPair;
     typedef std::multimap<int64, TxPair > TxItems;