Clamp colors after gamut xform in Ganesh

Fixes many blatant errors with glnarrow config

BUG=skia:

Change-Id: I729cda350ebce126bdac4eb41c91f30294e1c61e
Reviewed-on: https://skia-review.googlesource.com/5469
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed