smart_scrollbars fixes Matlab's listbox/editbox scrollbars to only show as needed

Syntax:
smart_scrollbars(hContainer)

Input parameters:
hContainer - optional handle to container (e.g., panel, tab or figure). Default = current figure (gcf)

Note: additional inputs may be specified and are ignored - this is useful for specifying smart_scrollbars as the target callback function (e.g., of the container's SizeChangedFcn). See example below.

Output parameters:
(none)

Examples:
smart_scrollbars; % fixes the scrollbars in all listboxes/editboxes in currrent figure
smart_scrollbars(hPanel); % fixes the scrollbars in all listboxes/editboxes in hPanel container
smart_scrollbars(hListbox); % fixes the scrollbars of the specified listbox
set(gcf,'SizeChangedFcn',@smart_scrollbars) % fix scrolling whenever the figure resizes

Technical explanation & details:
http://undocumentedmatlab.com/blog/smart-listbox-editbox-scrollbars

Warning:
This code heavily relies on undocumented and unsupported Matlab functionality. It works on Matlab 7+, but use at your own risk!

Bugs and suggestions:
Please send to Yair Altman (altmany at gmail dot com)