### Godot version

v4.0.beta9.official [e780dc332]

### System information

macOS Ventura 13.0.1 (Intel), Radeon Pro 580 8 GB

### Issue description

When setting the size of a SubViewport (that is inside the corresponding SubViewportContainer) to zero, the editor crashes instantly.

**But it only happens when I set the size of the SubViewport by sliding the values.**

You can see what happens in this video:


https://user-images.githubusercontent.com/91340577/209363880-503d3dff-80e1-4e9e-bb57-d059fdbfeed0.mp4

At the end of the video you can see the crash message of macOS reading: _Godot quit unexpectedly._

If I write the number zero (or any negative) to the values of the SubViewport size, the crash doesn't happens.

### Steps to reproduce

1. Add a SubViewportContainer
2. Add a SubViewport as a child of the SubViewportContainer
3. Set the size of the SubViewport to zero **by sliding** the X or the Y value.

### Minimal reproduction project

1. Open the project
2. Go to the Control.tscn scene
3. Select the SubViewport node
4. Slide the X or Y values of the size to zero

[SubViewportCrash.zip](https://github.com/godotengine/godot/files/10296101/SubViewportCrash.zip)
gui.forced_mouse_focus = false;
			}
			bool stopped = false;
			if (mouse_focus && mouse_focus->can_process()) {
				stopped = _gui_call_input(mouse_focus, mb);
			}
			if (stopped) {
				set_input_as_handled();
			}
		}
	}
	Ref<InputEventMouseMotion> mm = p_event;
	if (mm.is_valid()) {
		gui.key_event_accepted = false;
		Point2 mpos = mm->get_position();
		
		if (!gui.drag_attempted && gui.mouse_focus && (mm->get_button_mask().has_flag(MouseButtonMask::LEFT))) {
			gui.drag_accum += mm->get_relative();
			float len = gui.drag_accum.length();
			if (len > 10) {
				{ 
					CanvasItem *ci = gui.mouse_focus;
					while (ci) {
						Control *control = Object::cast_to<Control>(ci);
						if (control) {
							gui.dragging = true;
							gui.drag_data = control->get_drag_data(control->get_global_transform_with_canvas().affine_inverse().xform(mpos - gui.drag_accum));
							if (gui.drag_data.get_type() != Variant::NIL) {
								gui.mouse_focus = nullptr;
								gui.forced_mouse_focus = false;