Add support for _to_string virtual function overwrite in Pluginscript

modules/gdnative/include/pluginscript/godot_pluginscript.h

@@ -56,6 +56,7 @@ typedef struct {
 			int p_argcount, godot_variant_call_error *r_error);
 
 	void (*notification)(godot_pluginscript_instance_data *p_data, int p_notification);
+	godot_string (*to_string)(godot_pluginscript_instance_data *p_data, godot_bool *r_valid);
 
 	//this is used by script languages that keep a reference counter of their own
 	//you can make make Ref<> not die when it reaches zero, so deleting the reference

modules/gdnative/pluginscript/pluginscript_instance.cpp

@@ -93,6 +93,13 @@ void PluginScriptInstance::notification(int p_notification) {
 	_desc->notification(_data, p_notification);
 }
 
+String PluginScriptInstance::to_string(bool *r_valid) {
+	godot_string ret = _desc->to_string(_data, r_valid);
+	String str_ret = *(String *)&ret;
+	godot_string_destroy(&ret);
+	return str_ret;
+}
+
 Vector<ScriptNetData> PluginScriptInstance::get_rpc_methods() const {
 	return _script->get_rpc_methods();
 }

modules/gdnative/pluginscript/pluginscript_instance.h

@@ -63,6 +63,7 @@ public:
 	virtual Variant call(const StringName &p_method, const Variant **p_args, int p_argcount, Callable::CallError &r_error);
 
 	virtual void notification(int p_notification);
+	virtual String to_string(bool *r_valid);
 
 	virtual Ref<Script> get_script() const;