Reason for revert:
Reverting due to breakage in the Google3 import
Original issue's description:
> Add metal view, shaders and renderer.
>
> This CL submits standalone Metal view, renderer and shader.
>
> BUG=webrtc:7079
>
> Review-Url: https://codereview.webrtc.org/2651743007
> Cr-Commit-Position: refs/heads/master@{#16787}
> Committed: fc8c97f950TBR=magjed@webrtc.org,kthelgason@webrtc.org,tkchin@webrtc.org,haysc@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:7079
Review-Url: https://codereview.webrtc.org/2711003004
Cr-Commit-Position: refs/heads/master@{#16788}
b681aabdfc