Remove are_objects_directly_connected check

It's not necessary, since all of these objects are simple data objects
that will be passed as arguments to other functions. When we have to
pass through one of those functions we can just serialize the objects at
that point.

src/common/serialization/vst3/host-context-proxy.h

@@ -97,15 +97,6 @@ class Vst3HostContextProxy : public YaHostApplication {
         return arguments.owner_instance_id;
     }
 
-    /**
-     * Used to shortcut calls to
-     * `IHostApplication::createInstance(IMessage::iid, IMessage::iid, &obj)`
-     * when two objects (a processor and a controller instance, for example) are
-     * directly connected. This way we don't have to proxy the message created
-     * by the host, which can save a lot of resoruces.
-     */
-    std::atomic_bool are_objects_directly_connected = false;
-
    private:
     ConstructArgs arguments;
 };