Comma-separated lists (e.g. "<length>#") was added to the spec. https://drafts.css-houdini.org/css-properties-values-api-1/#supported-syntax-strings
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/3c4a1ee36e14d639e105f270d4080afe6d941cdb commit 3c4a1ee36e14d639e105f270d4080afe6d941cdb Author: Anders Hartvoll Ruud <andruud@chromium.org> Date: Mon Jul 09 13:57:18 2018 [css-properties-values-api] Support comma-separated lists. This adds support for syntax strings like "<length>#". R=chrishtr@chromium.org Bug: 859509 Change-Id: Ifd1ec986e5e11e8d00dfa5956f174616be857512 Reviewed-on: https://chromium-review.googlesource.com/1122625 Commit-Queue: Anders Ruud <andruud@chromium.org> Reviewed-by: Chris Harrelson <chrishtr@chromium.org> Cr-Commit-Position: refs/heads/master@{#573293} [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/WebKit/LayoutTests/external/wpt/css/css-properties-values-api/registered-property-computation.html [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/core/animation/css_interpolation_types_map.cc [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/core/css/css_syntax_descriptor.cc [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/core/css/css_syntax_descriptor.h [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/core/css/css_value_list.h [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/core/css/resolver/style_builder_converter.cc [modify] https://crrev.com/3c4a1ee36e14d639e105f270d4080afe6d941cdb/third_party/blink/renderer/platform/runtime_enabled_features.json5
Comment 1 by andruud@chromium.org
, Jul 4