Metal: Remove invalid ESSL 1.00 texture functions * 1D textures are not supported in GLSL ES * 2D textures do not support sampling with 3-component coordinates * Metal backend does not support rectangle texture type * Cubemap textures do not support sampling with projection Bug: angleproject:368059227 Change-Id: Iec33f4293d995b9f244274338d444604ffd23249 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5872915 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>