Generate subgroup StyleSurroundData in ComputedStyle.
StyleSurroundData is a class that contains the values of the offset,
margin, padding and border properties. This patch generates this class
as a nested class inside ComputedStyle. We add an extra key in
CSSProperties.json5 called 'field_group' that specifies the name of the
group that the field is in. Fields with the same field_group are grouped
together into a nested class.
A few caveats:
- Causes perf regression because it doesn't exploit sharing of groups.
The fix is in a dependent patch (to avoid bloating this CL). We
will land the fix right after this patch is landed.
https://codereview.chromium.org/2826633002
- We generate 'border' as 'storage_only', because it is a shorthand
and not a CSS property.
- Subgroups are currently generated as nested classes of ComputedStyle,
but this makes the code difficult to read. This may change in the
future (such as putting subgroups in a ::detail namespace).
- We don't ASSERT_SIZE on subgroups yet.
Diff of generated files:
https://gist.github.com/darrnshn/876c8171fd134b373f28ca23e821d28f/revisions
BUG=628043
Review-Url: https://codereview.chromium.org/2786883002
Cr-Commit-Position: refs/heads/master@{#467239}
17 files changed
