### Godot version

4.0-rc6

### System information

Fedora 37, Mesa Intel ADL GT2

### Issue description

Code that works as expected at runtime fails with Nil references to (assigned) exported vars in the editor:

![tool_global_position_error](https://user-images.githubusercontent.com/364501/222031460-ffb1ecbd-5175-4a42-8470-25285ba5f821.png)


### Steps to reproduce

Try to access the `global_position` of a `Node3D` that's assigned to an exported var.

See that it works at runtime.

See that it errors in the editor with:

> Invalid get index 'global_position' (on base: 'Nil').

### Minimal reproduction project

[tool_test.zip](https://github.com/godotengine/godot/files/10856640/tool_test.zip)

ClassDB::bind_method(D_METHOD("get_node_count"), &SceneState::get_node_count);
	ClassDB::bind_method(D_METHOD("get_node_type", "idx"), &SceneState::get_node_type);
	ClassDB::bind_method(D_METHOD("get_node_name", "idx"), &SceneState::get_node_name);
	ClassDB::bind_method(D_METHOD("get_node_path", "idx", "for_parent"), &SceneState::get_node_path, DEFVAL(false));
	ClassDB::bind_method(D_METHOD("get_node_owner_path", "idx"), &SceneState::get_node_owner_path);
	ClassDB::bind_method(D_METHOD("is_node_instance_placeholder", "idx"), &SceneState::is_node_instance_placeholder);
	ClassDB::bind_method(D_METHOD("get_node_instance_placeholder", "idx"), &SceneState::get_node_instance_placeholder);
	ClassDB::bind_method(D_METHOD("get_node_instance", "idx"), &SceneState::get_node_instance);
	ClassDB::bind_method(D_METHOD("get_node_groups", "idx"), &SceneState::_get_node_groups);
	ClassDB::bind_method(D_METHOD("get_node_index", "idx"), &SceneState::get_node_index);
	ClassDB::bind_method(D_METHOD("get_node_property_count", "idx"), &SceneState::get_node_property_count);
	ClassDB::bind_method(D_METHOD("get_node_property_name", "idx", "prop_idx"), &SceneState::get_node_property_name);
	ClassDB::bind_method(D_METHOD("get_node_property_value", "idx", "prop_idx"), &SceneState::get_node_property_value);
	ClassDB::bind_method(D_METHOD("get_connection_count"), &SceneState::get_connection_count);
	ClassDB::bind_method(D_METHOD("get_connection_source", "idx"), &SceneState::get_connection_source);
	ClassDB::bind_method(D_METHOD("get_connection_signal", "idx"), &SceneState::get_connection_signal);
	ClassDB::bind_method(D_METHOD("get_connection_target", "idx"), &SceneState::get_connection_target);
	ClassDB::bind_method(D_METHOD("get_connection_method", "idx"), &SceneState::get_connection_method);
	ClassDB::bind_method(D_METHOD("get_connection_flags", "idx"), &SceneState::get_connection_flags);
	ClassDB::bind_method(D_METHOD("get_connection_binds", "idx"), &SceneState::get_connection_binds);
	ClassDB::bind_method(D_METHOD("get_connection_unbinds", "idx"), &SceneState::get_connection_unbinds);
	BIND_ENUM_CONSTANT(GEN_EDIT_STATE_DISABLED);
	BIND_ENUM_CONSTANT(GEN_EDIT_STATE_INSTANCE);
	BIND_ENUM_CONSTANT(GEN_EDIT_STATE_MAIN);
	BIND_ENUM_CONSTANT(GEN_EDIT_STATE_MAIN_INHERITED);
}
SceneState::SceneState() {