### 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)
Ref<InputEventMouseButton> mb = p_event;
	
	if (mb.is_valid() && mb->is_pressed() && mb->get_button_index() == MouseButton::LEFT) {
		bool click_on_window = false;
		for (int i = gui.sub_windows.size() - 1; i >= 0; i--) {
			SubWindow sw = gui.sub_windows.write[i];
			
			Rect2i r = Rect2i(sw.window->get_position(), sw.window->get_size());
			if (!sw.window->get_flag(Window::FLAG_BORDERLESS)) {
				
				int title_height = sw.window->get_theme_constant(SNAME("title_height"));
				Rect2i title_bar = r;
				title_bar.position.y -= title_height;
				title_bar.size.y = title_height;
				if (title_bar.has_point(mb->get_position())) {
					click_on_window = true;
					int close_h_ofs = sw.window->get_theme_constant(SNAME("close_h_offset"));
					int close_v_ofs = sw.window->get_theme_constant(SNAME("close_v_offset"));
					Ref<Texture2D> close_icon = sw.window->get_theme_icon(SNAME("close"));
					Rect2 close_rect;
					close_rect.position = Vector2(r.position.x + r.size.x - close_h_ofs, r.position.y - close_v_ofs);
					close_rect.size = close_icon->get_size();
					if (gui.subwindow_focused != sw.window) {
						
						_sub_window_grab_focus(sw.window);
					}
					if (close_rect.has_point(mb->get_position())) {
						gui.subwindow_drag = SUB_WINDOW_DRAG_CLOSE;
						gui.subwindow_drag_close_inside = true; 
						gui.subwindow_drag_close_rect = close_rect;