Upgrade to the latest version of NS-3 (ns-3.27-22-g90fb309d5)

Change-Id: I01fa76eabc327a5638627b27bc51e6330d5ad221
Refs: #4311
diff --git a/tests/unit-tests/helper/ndn-stack-helper.t.cpp b/tests/unit-tests/helper/ndn-stack-helper.t.cpp
index a4fb8ed..04d5bba 100644
--- a/tests/unit-tests/helper/ndn-stack-helper.t.cpp
+++ b/tests/unit-tests/helper/ndn-stack-helper.t.cpp
@@ -32,7 +32,7 @@
   // setting default parameters for PointToPoint links and channels
   Config::SetDefault("ns3::PointToPointNetDevice::DataRate", StringValue("10Mbps"));
   Config::SetDefault("ns3::PointToPointChannel::Delay", StringValue("10ms"));
-  Config::SetDefault("ns3::DropTailQueue::MaxPackets", StringValue("20"));
+  Config::SetDefault("ns3::QueueBase::MaxPackets", UintegerValue(20));
 
   // Creating nodes
   NodeContainer nodes;