The spec requires us to store properties in their shorthand-expanded
form and in the "specified" order, removing duplicates prefering based
on "cascading order". We already enforced this in `set_property` but
not at creation time (e.g. in stylesheets) or in `set_css_text` (e.g.
updating style attribute).
This commit enforces the spec requirements at all the relevant points.
We no longer include logical properties in the return value of
`getComputedStyle` as they are mapped to their physical equivalents in
`StyleComputer::for_each_property_expanding_shorthands`, but resolving
that requires a relatively large rework of how we handle logical
properties, (namely moving when we map them to their physical
equivalents from parse time to style computation time).
This also exposes two false positive tests in
wpt-import/css/cssom/border-shorthand-serialization.html related to us
not yet supporting the border-image css property.
This exposed a few bugs which caused the following tests to behave
incorrectly:
- `tab-size-text-wrap.html`: This previously relied on a bug where we
incorrectly treated `white-space: pre` as allowing text wrapping. The
fix here is to implement the text-wrap CSS shorthand property.
- `execCommand-preserveWhitespace.html`: We don't correctly serialize
shorthand properties. This is covered by an existing FIXME in
`CSSStyleProperties::serialized()`
- `white-space-shorthand.html`: The last 5 subtests here fail as we
don't correctly handle shorthand properties in
`CSSStyleProperties::remove_property()`. This is covered by an
existing FIXME in said function.
This fixes one source of flakiness on WPT (of many) where we wouldn't
recompute style after programmatically altering the contents of a style
sheet, but instead had to wait for something else to cause invalidation.
The regression in the "conditional-CSSGroupingRule" test is we now fail
the "inserting an `@import`" subtests differently and the subtests
aren't independent. Specifically, we don't yet implement the checks in
`CSSRuleList::insert_a_css_rule()` that reject certain rules from being
inserted. Previously we didn't insert the `@import` rule because we
failed to parse its relative URL. Now we parse it correctly, we end up
inserting it.
