Fix the signature of the overload returning row and column which got corrupted during transition to Doxygen and document the overload returning the position as well. Also document all the parameters. Closes #12954. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67159 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775