### 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)

value = p_flag;
	queue_redraw();
}
void EditorPropertyLayersGrid::_bind_methods() {
	ADD_SIGNAL(MethodInfo("flag_changed", PropertyInfo(Variant::INT, "flag")));
	ADD_SIGNAL(MethodInfo("rename_confirmed", PropertyInfo(Variant::INT, "layer_id"), PropertyInfo(Variant::STRING, "new_name")));
}
void EditorPropertyLayers::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_ENTER_TREE:
		case NOTIFICATION_THEME_CHANGED: {
			button->set_texture_normal(get_theme_icon(SNAME("GuiTabMenuHl"), SNAME("EditorIcons")));
			button->set_texture_pressed(get_theme_icon(SNAME("GuiTabMenuHl"), SNAME("EditorIcons")));
			button->set_texture_disabled(get_theme_icon(SNAME("GuiTabMenu"), SNAME("EditorIcons")));
		} break;
	}
}
void EditorPropertyLayers::_set_read_only(bool p_read_only) {
	button->set_disabled(p_read_only);
	grid->set_read_only(p_read_only);
}
void EditorPropertyLayers::_grid_changed(uint32_t p_grid) {
	emit_changed(get_edited_property(), p_grid);
}
void EditorPropertyLayers::update_property() {
	uint32_t value = get_edited_property_value();
	grid->set_flag(value);
}
void EditorPropertyLayers::setup(LayerType p_layer_type) {