### 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
}
			if (rtl) {
				item_rect.position.x = get_size().width - item_rect.position.x - item_rect.size.x;
			}
			Point2i text_pos = item_rect.position;
			text_pos.y += Math::floor((item_rect.size.y - p_item->cells[i].text_buf->get_size().y) / 2);
			int text_width = p_item->cells[i].text_buf->get_size().x;
			switch (p_item->cells[i].mode) {
				case TreeItem::CELL_MODE_STRING: {
					draw_item_rect(p_item->cells.write[i], item_rect, col, icon_col, outline_size, font_outline_color);
				} break;
				case TreeItem::CELL_MODE_CHECK: {
					Ref<Texture2D> checked = theme_cache.checked;
					Ref<Texture2D> unchecked = theme_cache.unchecked;
					Ref<Texture2D> indeterminate = theme_cache.indeterminate;
					Point2i check_ofs = item_rect.position;
					check_ofs.y += Math::floor((real_t)(item_rect.size.y - checked->get_height()) / 2);
					if (p_item->cells[i].indeterminate) {
						indeterminate->draw(ci, check_ofs);
					} else if (p_item->cells[i].checked) {
						checked->draw(ci, check_ofs);
					} else {
						unchecked->draw(ci, check_ofs);
					}
					int check_w = checked->get_width() + theme_cache.h_separation;
					text_pos.x += check_w;
					item_rect.size.x -= check_w;
					item_rect.position.x += check_w;
					draw_item_rect(p_item->cells.write[i], item_rect, col, icon_col, outline_size, font_outline_color);
				} break;