Revert "SkColorSpace: remove named API, add gamut API"

Revert "SkColorSpace: remove named API, add gamut API"

This reverts commit ecaaf6f1c156e5690200322fc2636380c1f63dd8.

Reason for revert: Breaks everything

Original change's description:
> SkColorSpace: remove named API, add gamut API
>
> BUG=skia:
>
> Change-Id: I01c5e1874c9a034febc64e25b3aaafb5050393a6
> Reviewed-on: https://skia-review.googlesource.com/8021
> Reviewed-by: Brian Osman <brianosman@google.com>
> Reviewed-by: Mike Reed <reed@google.com>
> Commit-Queue: Matt Sarett <msarett@google.com>
>

TBR=msarett@google.com,brianosman@google.com,reed@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Change-Id: Ief5a0a4eeabe75a21f7512e23fc15309151066c4
Reviewed-on: https://skia-review.googlesource.com/8127
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Matt Sarett <msarett@google.com>