This is the GLES3 sampler object API trivially backported to GLES2,
because it allows for simpler/better support in glamor and mutter.
The only code change we need is adding these to the generated dispatch
tables for ES2 contexts. The interactions with EXT_shadow_samplers,
EXT_texture_filter_anisotropic and EXT_texture_sRGB_decode are already
in place before this change, and OES_texture_border_clamp is always
supported in Mesa.
Reviewed-by: Zoltán Böszörményi <zboszor@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Signed-off-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2440>
