* Source/cairo/CairoContext.m:
* Source/cairo/CairoSurface.m:
* Source/cairo/XGCairoModernSurface.m:
* Headers/cairo/XGCairoModernSurface.h:
* Headers/cairo/CairoSurface.h: New cairo surface which uses
cairo_surface_create_similar to create a back buffer which
has an alpha channel, even if the X server doesn't support
surfaces with alpha. This new surface is also made the default
since this seems to be the recommended way to double buffer
with cairo.
git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/back/trunk@33978 72102866-910b-0410-8b05-ffd578937521
