[Client] Do not copy strings in getLocalActor and getDedicatedActor

apps/openmw/mwmp/Cell.cpp

@@ -434,12 +434,12 @@ void Cell::uninitializeDedicatedActors()
     dedicatedActors.clear();
 }
 
-LocalActor *Cell::getLocalActor(std::string actorIndex)
+LocalActor *Cell::getLocalActor(const std::string &actorIndex)
 {
     return localActors.at(actorIndex);
 }
 
-DedicatedActor *Cell::getDedicatedActor(std::string actorIndex)
+DedicatedActor *Cell::getDedicatedActor(const std::string &actorIndex)
 {
     return dedicatedActors.at(actorIndex);
 }

apps/openmw/mwmp/Cell.hpp

@@ -36,8 +36,8 @@ namespace mwmp
         void uninitializeLocalActors();
         void uninitializeDedicatedActors();
 
-        virtual LocalActor *getLocalActor(std::string actorIndex);
-        virtual DedicatedActor *getDedicatedActor(std::string actorIndex);
+        virtual LocalActor *getLocalActor(const std::string &actorIndex);
+        virtual DedicatedActor *getDedicatedActor(const std::string &actorIndex);
 
         bool hasLocalAuthority();
         void setAuthority(const RakNet::RakNetGUID& guid);