Even though most compilers just ignore this, it's just wrong and if you
do get warnings about header files, they can become quite overwhelming.
Forward port of r70163.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70165 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Buttons had a border of wxBORDER_NONE resulting in wxButton::DoDraw not drawing the button's border. Fixed by adding wxAnyButton::GetDefaultBorder() for wxUniv which returns wxBORDER_STATIC. Regression since r67931.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68900 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775