Revert of New GM that exercises gamma-correctness in various parts of the pipeline. (patchset #4 id:60001 of https://codereview.chromium.org/1734983003/ )

Reason for revert:
Testing revert to fix MacMini?

Original issue's description:
> New GM that exercises gamma-correctness in various parts of the pipeline.
>
> Attempts to render 50% grey through many different techniques. Only the first one (black/white dither) is guaranteed to be correct. This serves as ground-truth for all the others (independent of whatever your display may or may not be doing when viewing the output of the GM).
>
> Current tests:
> - Texture bilerp
> - Texture scale (ie mipmaps)
> - Simple paint color
> - Gradient
> - A handful of Xfer modes
> - 50% grey bitmaps, both linear and sRGB
>
> Also includes a bug-fix for sRGB -> Linear bitmap case
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1734983003
>
> Committed: https://skia.googlesource.com/skia/+/9f73a71eec0eb54783f2dcad009aae6aafbe38d5

TBR=bsalomon@google.com,reed@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1744533002
5 files changed