### 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)

float rel = mm->get_relative().x;
		if (rel == 0) {
			return;
		}
		if (flip) {
			rel = -rel;
		}
		float val = get_edited_property_value();
		bool sg = val < 0;
		val = Math::absf(val);
		val = Math::log(val) / Math::log((float)2.0);
		
		val += rel * 0.05;
		val = Math::pow(2.0f, val);
		if (sg) {
			val = -val;
		}
		
		
		if (Math::is_zero_approx(val)) {
			val = 0.00001;
		}
		
		
		val = CLAMP(val, -1'000'000, 1'000'000);
		emit_changed(get_edited_property(), val);
		easing_draw->queue_redraw();
	}
}
void EditorPropertyEasing::_draw_easing() {