Default constructing a wxRegion created an object that unexpectedly passed
IsOk() test in wxOSX. This was completely unexpected so don't do this and
leave default constructed wxRegion invalid, as in the other ports.
Update DoCombine() to be able to deal with the case of an invalid source
region in a way consistent with the other ports.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@69459 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Fixed commented names (path, filename, and extension) of files in include/ and src/. Prepended the names in src/ with "src/" everywhere, while starting those in include/wx/ with "wx/".
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67254 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
