### 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)
Ref<InputEventKey> k = p_ev;
		if (k.is_valid() && k->is_pressed() && !k->is_echo() && debugger_stop_shortcut->matches_event(k)) {
			EngineDebugger::get_singleton()->send_message("request_quit", Array());
		}
	}
	if (exclusive_child != nullptr) {
		if (!is_embedding_subwindows()) { 
			return;
		}
	}
	emit_signal(SceneStringNames::get_singleton()->window_input, p_ev);
	push_input(p_ev);
	if (!is_input_handled()) {
		push_unhandled_input(p_ev);
	}
}
void Window::_window_input_text(const String &p_text) {
	push_text_input(p_text);
}
void Window::_window_drop_files(const Vector<String> &p_files) {
	emit_signal(SNAME("files_dropped"), p_files);
}
Viewport *Window::get_parent_viewport() const {
	if (get_parent()) {
		return get_parent()->get_viewport();
	} else {
		return nullptr;
	}
}
Window *Window::get_parent_visible_window() const {