menubar and populates it later. Since this is (or at least was)
a valid way to use wxMenuBar before that, we need to recalculate
the size whenever it might change. (We probably need to do it
anyway for this to be completely useful). This patch isn't the
cleanest or most efficient way to do that, but it's a minimal
change on a new feature that at least restores compatibility.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@17417 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
292cc8c93e