Revert of expand unitests for color4f (patchset #1 id:1 of https://codereview.chromium.org/1622893002/ )

Reason for revert:
leaking shadercontext in test

Original issue's description:
> expand unitests for color4f
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1622893002
>
> TBR=
>
> Committed: https://skia.googlesource.com/skia/+/fac684502b6047ffc7dc2e59bd7e5a7cbfa5bf78

TBR=
# 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/1622923002
5 files changed