The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5893d66e0e4cc0d37332e2c4e02ba36885823ea2

commit 5893d66e0e4cc0d37332e2c4e02ba36885823ea2
Author: fmalita <fmalita@chromium.org>
Date: Tue Mar 28 22:30:52 2017

Conic gradient parsing support

Add support for CSS Image Values Level 4 [repeating-]conic-gradient parsing,
based on https://drafts.csswg.org/css-images-4/#conic-gradients.

The feature is behind an experimental flag, pending full implementation and
shipping approval.

BUG= 705991 

Review-Url: https://codereview.chromium.org/2775103002
Cr-Commit-Position: refs/heads/master@{#460225}

[add] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/LayoutTests/fast/gradients/conic-gradient-parsing.html
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSGradientValue.cpp
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSGradientValue.h
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSImageGeneratorValue.cpp
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSValue.cpp
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSValue.h
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/CSSValueKeywords.json5
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/core/css/parser/CSSPropertyParserHelpers.cpp
[modify] https://crrev.com/5893d66e0e4cc0d37332e2c4e02ba36885823ea2/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5