skcms→9ff49a5 use GaussNewton for 7-parameter approx

Change-Id: I04894e17378cfbc982a11854a48217b63a2534ca
Reviewed-on: https://skia-review.googlesource.com/120161
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
7 files changed