In listaddressgroupings push down the IsMine check to run on each input.

This avoids a potential crash when trying to read the scrippubkeys on
transactions where the first input IsMine but some of the rest are not
when running listaddressgroupings.

src/wallet.cpp

@@ -1664,30 +1664,39 @@ set< set<CTxDestination> > CWallet::GetAddressGroupings()
     {
         CWalletTx *pcoin = &walletEntry.second;
 
-        if (pcoin->vin.size() > 0 && IsMine(pcoin->vin[0]))
+        if (pcoin->vin.size() > 0)
         {
+            bool any_mine = false;
             // group all input addresses with each other
             BOOST_FOREACH(CTxIn txin, pcoin->vin)
             {
                 CTxDestination address;
+                if(!IsMine(txin)) /* If this input isn't mine, ignore it */
+                    continue;
                 if(!ExtractDestination(mapWallet[txin.prevout.hash].vout[txin.prevout.n].scriptPubKey, address))
                     continue;
                 grouping.insert(address);
+                any_mine = true;
             }
 
             // group change with input addresses
+            if (any_mine)
+            {
                BOOST_FOREACH(CTxOut txout, pcoin->vout)
                    if (IsChange(txout))
                    {
-                    CWalletTx tx = mapWallet[pcoin->vin[0].prevout.hash];
                        CTxDestination txoutAddr;
                        if(!ExtractDestination(txout.scriptPubKey, txoutAddr))
                            continue;
                        grouping.insert(txoutAddr);
                    }
+            }
+            if (grouping.size() > 0)
+            {
                 groupings.insert(grouping);
                 grouping.clear();
             }
+        }
 
         // group lone addrs by themselves
         for (unsigned int i = 0; i < pcoin->vout.size(); i++)