### Godot version

4.0 beta 10

### System information

Windows 11 Vulkan

### Issue description

Looked through the issues list, but couldn't find something like this, sorry in advance if this has already been reported.

There is a few cases (in the pictures below) where list of Actions in Input Map may not always show a scrollbar even if the actions list overflows (I imagine this could also happen for the widget that Input Map uses).

![image](https://user-images.githubusercontent.com/39958198/210003566-cf60dbaf-921f-485b-b0a9-51ffc28d0244.png)

![New Bitmap image](https://user-images.githubusercontent.com/39958198/210004079-8eb2e6a1-0cf5-4a7c-8905-a4e3cfd0ec5d.png)

![image](https://user-images.githubusercontent.com/39958198/210004165-a6b6790b-248a-4f68-b4d0-b44b25afdf4f.png)

![image](https://user-images.githubusercontent.com/39958198/210004537-aca52194-a464-48b9-b818-24782706de45.png)


### Steps to reproduce

The pictures are clearer than anything I could write here: "a picture is worth 1000 words"

### Minimal reproduction project

N/A
ERR_FAIL_INDEX_V(p_column, columns.size(), TEXT_DIRECTION_INHERITED);
	return columns[p_column].text_direction;
}
void Tree::set_column_title_language(int p_column, const String &p_language) {
	ERR_FAIL_INDEX(p_column, columns.size());
	if (columns[p_column].language != p_language) {
		columns.write[p_column].language = p_language;
		update_column(p_column);
		queue_redraw();
	}
}
String Tree::get_column_title_language(int p_column) const {
	ERR_FAIL_INDEX_V(p_column, columns.size(), "");
	return columns[p_column].language;
}
Point2 Tree::get_scroll() const {
	Point2 ofs;
	if (h_scroll->is_visible_in_tree()) {
		ofs.x = h_scroll->get_value();
	}
	if (v_scroll->is_visible_in_tree()) {
		ofs.y = v_scroll->get_value();
	}
	return ofs;
}
void Tree::scroll_to_item(TreeItem *p_item, bool p_center_on_item) {