Add support for SDL_GL_CONTEXT_NO_ERROR.

Allows graphics drivers to run with reduced overhead.

src/sdl2/video.rs

@@ -295,6 +295,9 @@ pub mod gl_attr {
 
         (SDL_GL_FRAMEBUFFER_SRGB_CAPABLE, set_framebuffer_srgb_compatible, framebuffer_srgb_compatible, bool,
             "requests sRGB capable visual; defaults to false (>= SDL 2.0.1)")
+
+        (SDL_GL_CONTEXT_NO_ERROR, set_context_no_error, context_no_error, bool,
+            "disables OpenGL error checking; defaults to false (>= SDL 2.0.6)")
     }
 
     /// **Sets** the OpenGL context major and minor versions.