From the CSS token side, we already have these in FlyString form. From
the generated code side, we can easily return FlyStrings instead of
StringViews. So, let's do that, and save some work converting back and
forth.
Some properties like `justify-items`, `grid`, or `display` do affect
layout, but their used values can be obtained without performing a
layout calculation.
This change introduces a new helper,
`property_needs_layout_for_getcomputedstyle()`, specifically for use by
`CSSStyleProperties::property()`. It returns true only for properties
such as `width`, `height`, `margin`, `padding`, `top`, and `left`, where
an up-to-date layout is required to return the correct used value.
As noted, the chunk of this method that deals with animations could do
with some helpers on AbstractElement, but I'm leaving that until it's
clearer how animations and pseudo-elements should interact.
This doesn't need all of Selector.h and its various includes, it just
needs the PseudoElement enum.
StringStyleValue.h was transitively including ComponentValue.h through
this, so it now includes it directly.
Generating boilerplate is nice! This also has the bonus that we're more
correct: I included all the units listed in the spec before,
(see https://drafts.css-houdini.org/css-typed-om-1/#numeric-factory )
but we're supposed to exactly include ones for the units we support:
> If an implementation supports additional CSS units that do not have a
corresponding method in the above list, but that do correspond to one
of the existing CSSNumericType values, it must additionally support
such a method, named after the unit in its defined canonical casing,
using the generic behavior defined above.
> If an implementation does not support a given unit, it must not
implement its corresponding method from the list above.
Now, our factory functions will exactly match the units we support.
The changed test result is partly the order being different, and partly
that the container-query units are no longer included as we don't
actually support them.
Transitions apply after logical properties are mapped to their physical
counterparts so we should apply this mapping to `transition` properties
Gains us 20 WPT tests.
Using longhands rather than expanded longhands meant for instance that
we wouldn't transition `border-top-width` if we had `border` as the
transition property.
If we are interpolating between a dimension and a percentage value and
the dimension component is 0, we now return a percentage value rather
than a `calc()` value.
This updates `background-blend-mode`, `mix-blend-mode`, and `isolation`
to be animation type `discrete` rather than `none`. This reflects
169b0e1 but isn't reflected
on the published spec as the published spec is out of date - see
https://github.com/w3c/fxtf-drafts/issues/547
Gains us 26 WPT tests.
All remaining failing subtests in border-image-width-interpolation.html
are related to incorrect handling of mixed dimension and percentage
interpolation and are fixed by #6142.
