Misc changes that might not be needed

Author: caitp

NativeScript/NativeScript.mm

@@ -7,6 +7,8 @@
 #include "runtime/Runtime.h"
 #include "runtime/Tasks.h"
 
+#include <memory>
+
 using namespace v8;
 using namespace tns;
 

NativeScript/runtime/ArgConverter.mm

@@ -3,7 +3,6 @@
 #include "ArgConverter.h"
 #include "NativeScriptException.h"
 #include "DictionaryAdapter.h"
-#include "ObjectManager.h"
 #include "Interop.h"
 #include "Helpers.h"
 #include "Runtime.h"