SkRasterPipeline impl for 2-stop linear gradients


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

Change-Id: Ia2b630cf9c0826fbfc3342707c005030d0529bbc
Reviewed-on: https://skia-review.googlesource.com/7186
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
5 files changed