Move some of the difference-transmission unit tests from lua to C++

luprex/cpp/core/luasnap.cpp

@@ -27,17 +27,6 @@ public:
 LuaSnap::LuaSnap() {
     state_ = LuaCoreStack::newstate(eng::l_alloc);
     LuaExtStack LS(state_);
-
-    // Create the persist table and the unpersist table.
-    //
-    // These tables need to contain all C functions.  Whenever
-    // the source module inserts a C function into the lua environment,
-    // it also needs to register the C function in these tables.
-    //
-    // I don't think anything else needs to go in these tables.
-    //
-    LS.rawset(LuaRegistry, "persist", LuaNewTable);
-    LS.rawset(LuaRegistry, "unpersist", LuaNewTable);
 }
 
 LuaSnap::~LuaSnap() {