wxBitmap uses CGImage instead of NSImage internally and the conversion looses NSImage metadata. In particular, it looses the "template" attribute, which is set for files ending with "Template" and loaded trough wxArtProvider. This change makes it easy to use template images with native controls such as the toolbar. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78016 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775