Enable high-quality linear gradients
(remove SK_SUPPORT_LEGACY_LINEAR_GRADIENT_TABLE)
Start using Skia's analytical linear gradients (software-only).
The new implementation addresses a couple of fundamental issues present
in the old/LUT-based approach:
* inexact (or blurred) hard color stops
* banding artifacts
BUG=558622,41756,98436,117140,135568,140208,152706,177293,180783,229561,233879,271552,317502,375630,403959,414254,419344,476548,486063,543625,skia:1077
R=reed@google.com,chrishtr@chromium.org
Review URL: https://codereview.chromium.org/1457783005
Cr-Commit-Position: refs/heads/master@{#361476}
3 files changed
