LessTif 0.93 does not hang in wxWindow::ChangeFont as 0.87 did:

  LessTif 0.93 does not hang in wxWindow::ChangeFont as 0.87 did:
enable chainging window font again.
  Set/reset MappedWhenManaged flag when showing/hiding a window, otherwise,
since some common operations (moving, adding items to a listbox, ...) do
a Unmanage-Manage pair, calling Hide and then (for example) SetSize would
show the window again.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@18450 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775