fw: pass const shared_ptr<pit::Entry>& to Strategy triggers

refs #3205

Change-Id: I8f227c57ee6733526f0569de81f20677210cafa4
diff --git a/daemon/fw/broadcast-strategy.hpp b/daemon/fw/broadcast-strategy.hpp
index 1f868b5..1ef781c 100644
--- a/daemon/fw/broadcast-strategy.hpp
+++ b/daemon/fw/broadcast-strategy.hpp
@@ -37,12 +37,12 @@
 class BroadcastStrategy : public MulticastStrategy
 {
 public:
+  explicit
   BroadcastStrategy(Forwarder& forwarder, const Name& name = STRATEGY_NAME);
 
   virtual void
-  afterReceiveInterest(const Face& inFace,
-                       const Interest& interest,
-                       shared_ptr<pit::Entry> pitEntry) override;
+  afterReceiveInterest(const Face& inFace, const Interest& interest,
+                       const shared_ptr<pit::Entry>& pitEntry) override;
 
 public:
   static const Name STRATEGY_NAME;