NAME
        HideAllListBrowserChildren -- Hide all children in a ListBrowser.

    SYNOPSIS
        VOID HideAllListBrowserChildren(struct List *);
        HideAllListBrowserChildren(list);

    FUNCTION
        Hides all children in a hierarchical ListBrowser, "collapsing" all
        generations so that only root generation nodes are shown.

        Note that as with any modifications to a ListBrowser list, the list
        MUST be detached to the listbrowser at the time of modification.

    INPUTS
        list - a list of ListBrowser nodes, not currently attached to a
            ListBrowser.