Correctly use DECLARE_DYNAMIC_CLASS for the classes that are supposed to be
dynamically creatable as using DECLARE_CLASS doesn't work any longer after the
last commit.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67880 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775