[cairo] Can't build cairo via Makefile on win32

[Andrej Mitrovic]

Ok, now I need to ask where do I fetch the dependencies for the
GL-backend? I only found some references to Quartz in the readme
files, but that seems to be deprecated.

When I try to build with CAIRO_HAS_GL_SURFACE=1, I get back:

g:\cairobuild\cairo\src\cairo-gl-gradient-private.h(49) : fatal error C1083: Can
not open include file: 'GL/glew.h': Invalid argument
make[1]: *** [release/cairo-gl-composite.obj] Error 2

There's a glew/GL/glew.h file, so maybe it's just an #include
mismatch? But I'm also seeing some other includes in the
cairo-gl-gradient-private.h file like "gl.h", which is not in the
cairo sources.

Do I need to download these GL dependencies from somewhere?