Check for GLX_EXT_framebuffer_sRGB

[kvark]

This GLX code fails on some machines:

        if reqs.srgb {
            if extensions.split(' ').find(|&i| i == "GLX_ARB_framebuffer_sRGB").is_some() {
                out.push(ffi::glx_extra::FRAMEBUFFER_SRGB_CAPABLE_ARB as c_int);
                out.push(1);
            } else {
                return Err(());
            }
        }

glxinfo seems to not feature the ARB version but it does have the EXT one:

server glx vendor string: NVIDIA Corporation
server glx version string: 1.4
server glx extensions:
    GLX_ARB_context_flush_control, GLX_ARB_create_context, 
    GLX_ARB_create_context_profile, GLX_ARB_create_context_robustness, 
    GLX_ARB_fbconfig_float, GLX_ARB_multisample, GLX_EXT_buffer_age, 
    GLX_EXT_create_context_es2_profile, GLX_EXT_create_context_es_profile, 
    GLX_EXT_framebuffer_sRGB, GLX_EXT_stereo_tree, GLX_EXT_swap_control, 
    GLX_EXT_swap_control_tear, GLX_EXT_texture_from_pixmap, 
    GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_NV_copy_image, 
    GLX_NV_delay_before_swap, GLX_NV_float_buffer, 
    GLX_NV_multisample_coverage, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, 
    GLX_SGI_swap_control, GLX_SGI_video_sync
client glx vendor string: NVIDIA Corporation
client glx version string: 1.4
client glx extensions:
    GLX_ARB_context_flush_control, GLX_ARB_create_context, 
    GLX_ARB_create_context_profile, GLX_ARB_create_context_robustness, 
    GLX_ARB_fbconfig_float, GLX_ARB_get_proc_address, GLX_ARB_multisample, 
    GLX_EXT_buffer_age, GLX_EXT_create_context_es2_profile, 
    GLX_EXT_create_context_es_profile, GLX_EXT_fbconfig_packed_float, 
    GLX_EXT_framebuffer_sRGB, GLX_EXT_import_context, GLX_EXT_stereo_tree, 
    GLX_EXT_swap_control, GLX_EXT_swap_control_tear, 
    GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating, 
    GLX_NV_copy_buffer, GLX_NV_copy_image, GLX_NV_delay_before_swap, 
    GLX_NV_float_buffer, GLX_NV_multisample_coverage, GLX_NV_present_video, 
    GLX_NV_swap_group, GLX_NV_video_capture, GLX_NV_video_out, 
    GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, GLX_SGI_swap_control, 
    GLX_SGI_video_sync
GLX version: 1.4
GLX extensions:
    GLX_ARB_context_flush_control, GLX_ARB_create_context, 
    GLX_ARB_create_context_profile, GLX_ARB_create_context_robustness, 
    GLX_ARB_fbconfig_float, GLX_ARB_get_proc_address, GLX_ARB_multisample, 
    GLX_EXT_buffer_age, GLX_EXT_create_context_es2_profile, 
    GLX_EXT_create_context_es_profile, GLX_EXT_framebuffer_sRGB, 
    GLX_EXT_stereo_tree, GLX_EXT_swap_control, GLX_EXT_swap_control_tear, 
    GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating, 
    GLX_NV_copy_image, GLX_NV_delay_before_swap, GLX_NV_float_buffer, 
    GLX_NV_multisample_coverage, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer, 
    GLX_SGI_swap_control, GLX_SGI_video_sync

Perhaps, we could check for EXT there as well?

[tyoc213]

This is fixed on c68c0d9

[kvark]

Thanks!