Different fix for cursor inheritance and busy cursor/global cursor.
Previous work was not compatible with GTK < 2.18 and did not properly handle some cases
see #15801


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@75807 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775