### 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 (p_argcount < 1) {
		r_error.error = Callable::CallError::CALL_ERROR_TOO_FEW_ARGUMENTS;
		r_error.argument = 0;
		return;
	}
	if (p_args[0]->get_type() != Variant::STRING && p_args[0]->get_type() != Variant::STRING_NAME) {
		r_error.error = Callable::CallError::CALL_ERROR_INVALID_ARGUMENT;
		r_error.argument = 0;
		r_error.expected = Variant::STRING_NAME;
		return;
	}
	StringName method = *p_args[0];
	call_recursive(method, &p_args[1], p_argcount - 1, r_error);
}
void recursive_call_aux(TreeItem *p_item, const StringName &p_method, const Variant **p_args, int p_argcount, Callable::CallError &r_error) {
	if (!p_item) {
		return;
	}
	p_item->callp(p_method, p_args, p_argcount, r_error);
	TreeItem *c = p_item->get_first_child();
	while (c) {
		recursive_call_aux(c, p_method, p_args, p_argcount, r_error);
		c = c->get_next();
	}
}
void TreeItem::call_recursive(const StringName &p_method, const Variant **p_args, int p_argcount, Callable::CallError &r_error) {