Create wxMSWOwnerDrawnButton class which contains all of this code.
Currently the methods of this class are (still) implemented in
src/msw/control.cpp.
See #10137.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76459 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775