Which pretty much needs to be done together due to the amount of places
where they are compared together.
This also involves porting over StackOfOpenElements over to FlyString
from DeprecatedFly string to prevent a gazillion calls to
`.to_deprecated_fly_string` calls in HTMLParser.
Renaming the DeprecatedString version of this function to
Element::get_deprecated_attribute.
While performing this rename, port over functions where it is trivial to
do so to the Optional<String> version of this function.
By loading only the fonts actually used on a page, we can often avoid
making a lot of unnecessary requests and style invalidations.
This change makes initial loading of apple.com much faster.
Fixes https://github.com/SerenityOS/serenity/issues/20747
Now that shorthands use ShorthandStyleValue, the only bespoke code left
for them applies to CSS-wide keywords. We can automate expanding those,
so let's do so. :^)
For now, part of this is commented-out. Our current implementations of
`<mask>` and `<symbol>` rely on creating layout nodes, so they can't be
`display: none`.
The `to_string()` for this is modified a little from the original,
because we have to calculate what the layer-count is then, instead of
having it already calculated.
We were parsing these all right, but ignoring them in StyleComputer.
No test unfortunately, since we don't currently have a way to delay
the load event until a @font-face has been fully loaded. (Any test
of this right now would be flaky.)
In order to access the string's contents, use the new
`StringStyleValue::string_value()` method.
I think I found all the existing places that relied on
`StringStyleValue::to_string()` returning an unquoted string, but it's
hard to know for sure until things break.
This one is a bit fun because it can be `add(<integer>)` or `auto-add`,
but children have to inherit the computed value not the specified one.
We also have to compute it before computing the font-size, because of
`font-size: math` which will be implemented later.
This is a `<display-inside>` keyword added by the MathML spec, and has
the rough meaning of "display in the default way". It enables the
standard layout rules for each MathML element (and is ignored for
anything that isn't a MathML element).
I believe we'll need an actual MathML formatting context to do the
layout correctly, but we can at least support a couple of elements that
behave the same as HTML ones.
Resolving typed `attr()` functions is going to involve using more
internal Parser methods, so this is the simplest solution for that.
Also... resolving these is basically parsing them, so it makes more
sense for that process to live here.
This is just moving code, with minimal changes so it still works.
This is a bit iffy, but since <br> elements can't be implemented in
"just CSS" today, we should also exclude them from the blockification
algorithm. This is important, since <br> is expected to always have
inline-like behavior.
This is intended to annotate conversions from unknown floating-point
values to CSSPixels, and make it more obvious the fp value will be
rounded to the nearest fixed-point value.
In general it is not safe to convert any arbitrary floating-point value
to CSSPixels. CSSPixels has a resolution of 0.015625, which for small
values (e.g. scale factors between 0 and 1), can produce bad results
if converted to CSSPixels then scaled back up. In the worst case values
can underflow to zero and produce incorrect results.
This means StyleComputer::resolve_unresolved_style_value() always
returns a value, so we can change its return type.
However, it does still return an UnresolvedStyleValue sometimes, so we
can't remove those checks from the user code.
Note that we don't load the local font as specified, but at least we no
longer reject such src properties in the CSS parser.
This makes the custom fonts used on http://apple.com/ actually load. :^)
In case we've looked up the family name before and cached the result of
font fallback, we now invalidate any cached entries with the same family
name so that the next lookup may consider the newly downloaded font.
This avoids looking at every single installed typeface to see if there's
a family name match.
Fixes a large performance regression introduced when making
StyleComputer consider system fonts in CSS font fallback.
Regressed with 69a81243f5.
