It seems p2p-compactblocks.py fails randomly

From: https://travis-ci.org/bitcoin/bitcoin/jobs/163788152 from #8841
The PR is trivial and totally unrelated to compact block

```
p2p-compactblocks.py:
Initializing test directory /tmp/test3yd_2q3h/2
start_node: bitcoind started, waiting for RPC to come up
start_node: RPC succesfully started
MiniNode: Connecting to Bitcoin Node IP # 127.0.0.1:11016
Testing SENDCMPCT p2p message... 
Testing compactblock headers and shortIDs are correct...
Assertion failed: 
Stopping nodes
Not cleaning up dir /tmp/test3yd_2q3h/2
Failed
stderr:
  File "/home/travis/build/bitcoin/bitcoin/qa/rpc-tests/test_framework/test_framework.py", line 151, in main
    self.run_test()
  File "/home/travis/build/bitcoin/bitcoin/build/../qa/rpc-tests/p2p-compactblocks.py", line 614, in run_test
    self.test_compactblock_construction()
  File "/home/travis/build/bitcoin/bitcoin/build/../qa/rpc-tests/p2p-compactblocks.py", line 264, in test_compactblock_construction
    assert(self.test_node.last_cmpctblock is not None)
Pass: False, Duration: 7 s
```

{
            
            if (fListen && !IsInitialBlockDownload())
            {
                CAddress addr = GetLocalAddress(&pfrom->addr, pfrom->GetLocalServices());
                FastRandomContext insecure_rand;
                if (addr.IsRoutable())
                {
                    LogPrint("net", "ProcessMessages: advertising address %s\n", addr.ToString());
                    pfrom->PushAddress(addr, insecure_rand);
                } else if (IsPeerAddrLocalGood(pfrom)) {
                    addr.SetIP(pfrom->addrLocal);
                    LogPrint("net", "ProcessMessages: advertising address %s\n", addr.ToString());
                    pfrom->PushAddress(addr, insecure_rand);
                }
            }
            
            if (pfrom->fOneShot || pfrom->nVersion >= CADDR_TIME_VERSION || connman.GetAddressCount() < 1000)
            {
                pfrom->PushMessage(NetMsgType::GETADDR);
                pfrom->fGetAddr = true;
            }
            connman.MarkAddressGood(pfrom->addr);
        }
        pfrom->fSuccessfullyConnected = true;
        string remoteAddr;
        if (fLogIPs)
            remoteAddr = ", peeraddr=" + pfrom->addr.ToString();
        LogPrintf("receive version message: %s: version %d, blocks=%d, us=%s, peer=%d%s\n",
                  pfrom->cleanSubVer, pfrom->nVersion,