strip down SkICC.cpp

Most of SkICC{.h,.cpp} is unused and gone.

I've renamed the part that's left to SkWriteICCProfile() and tweaked its
API just a little, leaving SkICC:WriteToICC() a wrapper around it.

Most of the tests in ICCTest.cpp are moot and deleted, but a few looked
somewhat valuable so I've kept them with a little modification.

Change-Id: Ia1bb4c772af679885e17dac53d213c315ad0828c
Reviewed-on: https://skia-review.googlesource.com/127022
Auto-Submit: Mike Klein <mtklein@chromium.org>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
5 files changed