Allow numerical color spaces with legacy rendering

Bug: 720083
Change-Id: Ibd4dbf6ee95ac14857e8280a441f81976710e5e8
Reviewed-on: https://skia-review.googlesource.com/16700
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
6 files changed