### 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)

uint32_t value = get_edited_property_value();
	for (int i = 0; i < flags.size(); i++) {
		flags[i]->set_pressed((value & flag_values[i]) == flag_values[i]);
	}
}
void EditorPropertyFlags::setup(const Vector<String> &p_options) {
	ERR_FAIL_COND(flags.size());
	bool first = true;
	uint32_t current_val;
	for (int i = 0; i < p_options.size(); i++) {
		
		String option = p_options[i].strip_edges();
		if (option.is_empty()) {
			continue;
		}
		const int flag_index = flags.size(); 
		
		Vector<String> text_split = p_options[i].split(":");
		if (text_split.size() != 1) {
			current_val = text_split[1].to_int();
		} else {
			current_val = 1 << i;
		}
		flag_values.push_back(current_val);
		
		CheckBox *cb = memnew(CheckBox);
		cb->set_text(option);
		cb->set_clip_text(true);