add rescan bool to importprivkey to control whether to do a rescan after import

src/rpcdump.cpp

@@ -34,15 +34,21 @@ public:
 
 Value importprivkey(const Array& params, bool fHelp)
 {
-    if (fHelp || params.size() < 1 || params.size() > 2)
+    if (fHelp || params.size() < 1 || params.size() > 3)
         throw runtime_error(
-            "importprivkey <bitcoinprivkey> [label]\n"
+            "importprivkey <bitcoinprivkey> [label] [rescan=true]\n"
             "Adds a private key (as returned by dumpprivkey) to your wallet.");
 
     string strSecret = params[0].get_str();
     string strLabel = "";
     if (params.size() > 1)
         strLabel = params[1].get_str();
+
+    // Whether to perform rescan after import
+    bool fRescan = true;
+    if (params.size() > 2)
+        fRescan = params[2].get_bool();
+
     CBitcoinSecret vchSecret;
     bool fGood = vchSecret.SetString(strSecret);
 
@@ -62,8 +68,10 @@ Value importprivkey(const Array& params, bool fHelp)
         if (!pwalletMain->AddKey(key))
             throw JSONRPCError(RPC_WALLET_ERROR, "Error adding key to wallet");
 	
-        pwalletMain->ScanForWalletTransactions(pindexGenesisBlock, true);
-        pwalletMain->ReacceptWalletTransactions();
+        if (fRescan) {
+            pwalletMain->ScanForWalletTransactions(pindexGenesisBlock, true);
+            pwalletMain->ReacceptWalletTransactions();
+        }
     }
 
     return Value::null;