Make ResourceManager destructor virtual

components/resource/resourcemanager.cpp

@@ -13,6 +13,10 @@ namespace Resource
 
     }
 
+    ResourceManager::~ResourceManager()
+    {
+    }
+
     void ResourceManager::updateCache(double referenceTime)
     {
         mCache->updateTimeStampOfObjectsInCacheWithExternalReferences(referenceTime);

components/resource/resourcemanager.hpp

@@ -18,6 +18,7 @@ namespace Resource
     {
     public:
         ResourceManager(const VFS::Manager* vfs);
+        virtual ~ResourceManager();
 
         /// Clear cache entries that have not been referenced for longer than expiryDelay.
         virtual void updateCache(double referenceTime);