Refactors the Skia Gold-related code in //content/test/gpu/gpu_tests
to be the same as //build/android/pylib. All the code that interacts
with Gold is encapsulated in its own class, and users simply run one
method and check its output to perform an image comparison.
Also adds a bunch of unittests (also taken from //build/android/pylib)
since the split makes the code unittest-able.
Drive-by fixes a related TODO in //build/android since the same TODO
was fixed in the GPU code in this CL.
Bug: 1093994
Change-Id: Id2fe1506796695f258069334149550cfaea49f71
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2243718
Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#778514}
2df4e14530