title: Detect change in RadGrid item expand/collapse state
body: <p>I have a RadGrid displaying a hierarchical structure.  I want to save the expand/collapse state of each item in the grid so that when the user returns to the site, everything looks exactly as they left it.  I have code to save and restore the state of expanded/collapsed items, however, I now need a way to detect which item is currently being expanded/collapsed when the user clicks on the expand/collapse icon.  I know there's a command event, but there is no command argument nor does there seem to be any indication of which item's state is being changed.  Any ideas?</p>