Revert of Revert of Add gamma/sRGB tag to SkImageInfo (patchset #1 id:1 of https://codereview.chromium.org/525113005/)

Reason for revert:
Experiment to see resulting failures

Original issue's description:
> Revert of Add gamma/sRGB tag to SkImageInfo (patchset #1 id:1 of https://codereview.chromium.org/522813002/)
>
> Reason for revert:
> seems to be breaking layout tests in roll
>
> Original issue's description:
> > Add gamma/sRGB tag to SkImageInfo
> >
> > This reverts commit 64ba5fa1ff428858f803523257cd862f8b33423b.
> >
> > BUG=skia:
> >
> > Committed: https://skia.googlesource.com/skia/+/c89aa509d6a094bc1b18d73135343819903a9cfb
>
> TBR=reed@google.com
> NOTREECHECKS=true
> NOTRY=true
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/b44c1895afae516cb851cd1a0cea83343c354ee4

R=reed@google.com
TBR=reed@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: reed@chromium.org

Review URL: https://codereview.chromium.org/532583002
4 files changed