### 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)

int64_t val = get_edited_property_value();
	setting = true;
	spin->set_value(val);
	setting = false;
#ifdef DEBUG_ENABLED
	
	if (val != (int64_t)(double)(val)) {
		WARN_PRINT("Cannot reliably represent '" + itos(val) + "' in the inspector, value is too large.");
	}
#endif
}
void EditorPropertyInteger::_bind_methods() {
}
void EditorPropertyInteger::setup(int64_t p_min, int64_t p_max, int64_t p_step, bool p_hide_slider, bool p_allow_greater, bool p_allow_lesser, const String &p_suffix) {
	spin->set_min(p_min);
	spin->set_max(p_max);
	spin->set_step(p_step);
	spin->set_hide_slider(p_hide_slider);
	spin->set_allow_greater(p_allow_greater);
	spin->set_allow_lesser(p_allow_lesser);
	spin->set_suffix(p_suffix);
}
EditorPropertyInteger::EditorPropertyInteger() {
	spin = memnew(EditorSpinSlider);
	spin->set_flat(true);
	add_child(spin);
	add_focusable(spin);
	spin->connect("value_changed", callable_mp(this, &EditorPropertyInteger::_value_changed));
}
void EditorPropertyObjectID::_set_read_only(bool p_read_only) {