### Godot version

v4.0.beta17.official [c40020513]

### System information

macOS 13.0.1

### Issue description

When a `Control` node is over a `SubViewportContainer` (with a `SubViewport` as a child), both in Full Rect anchors, asking for the get_viewport().get_mouse_position() from a scene inside the `SubViewport` returns (0, 0) as the position of the mouse.

This wasn't happening in at least Beta 15. I was getting the mouse position without any problems before Beta 17. I didn't try Beta 16.

### Steps to reproduce

1. Create a `Control` node
2. Add two children: A `SubViewportContainer` and a `Control` node
3. Put both in Full Rect anchors so the `Control` node (child) is covering the `SubViewportContainer`
4. Ask for the get_viewport().get_mouse_position() from inside a scene of the `SubViewport`

As you can see in this screenshot: asking for the mouse position from inside the `Node2D` script always returns (0, 0).

<img width="1533" alt="SubViewportContainerIssue" src="https://user-images.githubusercontent.com/91340577/217051768-d9c2e8ad-40ca-4c6d-bb98-f6a7c9c6081f.png">

Only If the `Control` (child) mouse filtering is set to _Ignore_ you can get the mouse position. But with that you are losing the mouse inputs from that `Control` node.

You can find the setup of these nodes in the MRP.


### Minimal reproduction project

Run the main scene (control.tscn) and move the mouse around the screen. Look for the print in the Output tab.

[SubViewportMousePositionIssue.zip](https://github.com/godotengine/godot/files/10667894/SubViewportMousePositionIssue.zip)
String tooltip = _gui_get_tooltip(over, gui.tooltip_control->get_global_transform().xform_inv(mpos));
						tooltip = tooltip.strip_edges();
						if (tooltip.length() == 0) {
							_gui_cancel_tooltip();
						} else if (gui.tooltip_label) {
							if (tooltip == gui.tooltip_label->get_text()) {
								is_tooltip_shown = true;
							}
						} else {
							is_tooltip_shown = true; 
						}
					} else {
						_gui_cancel_tooltip();
					}
				}
				if (!is_tooltip_shown && over->can_process()) {
					if (gui.tooltip_timer.is_valid()) {
						gui.tooltip_timer->release_connections();
						gui.tooltip_timer = Ref<SceneTreeTimer>();
					}
					gui.tooltip_control = over;
					gui.tooltip_pos = over->get_screen_transform().xform(pos);
					gui.tooltip_timer = get_tree()->create_timer(gui.tooltip_delay);
					gui.tooltip_timer->set_ignore_time_scale(true);
					gui.tooltip_timer->connect("timeout", callable_mp(this, &Viewport::_gui_show_tooltip));
				}
			}
			mm->set_position(pos);
			Control::CursorShape cursor_shape = Control::CURSOR_ARROW;
			{