Auto merge of #1407 - bitcartel:master_bitcoin_7079, r=daira

Upstream patch: Prevent peer flooding inv request queue

https://github.com/bitcoin/bitcoin/pull/7079
5029698186445bf3cd69d0e720f019c472661bff
ebb25f4c23adbcb55796c402bafd6064a136f16f

src/main.cpp

@@ -4657,6 +4657,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
         bool fMissingInputs = false;
         CValidationState state;
 
+        pfrom->setAskFor.erase(inv.hash);
         mapAlreadyAskedFor.erase(inv);
 
         // Check for recently rejected (and do other quick existence checks)
@@ -5451,6 +5452,9 @@ bool SendMessages(CNode* pto, bool fSendTrickle)
                     pto->PushMessage("getdata", vGetData);
                     vGetData.clear();
                 }
+            } else {
+                //If we're not going to ask, don't expect a response.
+                pto->setAskFor.erase(inv.hash);
             }
             pto->mapAskFor.erase(pto->mapAskFor.begin());
         }