Reason for revert:
Broke bots
Original issue's description:
> Explicit control in tools of ANGLE frontend and backend
>
> Update the ANGLE test GL context, GrContextFactory, and config parsing to allow explicit control of ANGLE front/backend.
>
> This will allow us to explicitly test ES2 vs ES3 interfaces to ANGLE as well as D3D9, D3D11, and OpenGL backends.
>
> Also makes the angle api types valid in all builds (but will just fail when SK_ANGLE=1 or not on windows for the d3d backends).
>
> BUG=skia:5804
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2381033002
>
> Committed: https://skia.googlesource.com/skia/+/50094fb489543655df026be4e4f99e09e57a1f49TBR=brianosman@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:5804
Review-Url: https://codereview.chromium.org/2384483003
Update the ANGLE test GL context, GrContextFactory, and config parsing to allow explicit control of ANGLE front/backend.
This will allow us to explicitly test ES2 vs ES3 interfaces to ANGLE as well as D3D9, D3D11, and OpenGL backends.
Also makes the angle api types valid in all builds (but will just fail when SK_ANGLE=1 or not on windows for the d3d backends).
BUG=skia:5804
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2381033002
NOTREECHECKS=true
NOTRY=true
NOPRESUBMIT=true
Review-Url: https://codereview.chromium.org/2381033002
