Allow testglarea to work with legacy GL contexts
Allow testglarea to work with legacy GL contexts

Use the 1.30 GLSL shading language for the fragment and vertex shaders.

https://bugzilla.gnome.org/show_bug.cgi?id=756142

grubersjoe/adwaita,alexlarsson/gtk,grubersjoe/adwaita,grubersjoe/adwaita,alexlarsson/gtk,alexlarsson/gtk,alexlarsson/gtk,alexlarsson/gtk,grubersjoe/adwaita,grubersjoe/adwaita,grubersjoe/adwaita,grubersjoe/adwaita,alexlarsson/gtk,alexlarsson/gtk,grubersjoe/adwaita,alexlarsson/gtk