Reland "Add RasterPipeline implementation for SkColorSpaceXform"

This is initially turned on for Linux debug builds,
which allows us to start testing.

Chrome for Android is a really good candidate for
this (will appreciate the code size savings), but
I'd first like to run some tests to understand the
performance/size tradeoffs a little better.

BUG:660416

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD

Change-Id: Ifc80e663767df6bb767abb8b12b1ec5cec644ec5
Reviewed-on: https://skia-review.googlesource.com/5452
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
4 files changed