Per the CSS Namespaces spec, an empty string declared in an
@namespace rule represents no namespace.
Fixes WPT:
- css/css-namespaces/prefix-002.xml
- css/css-namespaces/prefix-003.xml
The CSS spec says the baseline of an inline-block should be the bottom
margin when either the overflow property is not 'visible' or there are
no in-flow line boxes. Previously, only the latter case was checked.
This fixes 1 WPT test:
https://wpt.live/css/css-align/baseline-of-scrollable-1a.html
This fixes an issue where text decorations (e.g. underlines) of text
split across multiple fragments would have unintended 1px gaps.
Gains us 2 WPT passes (imported)
Implements `::slotted()` to enough extent we could pass the imported WPT
test and make substantial layout correctness improvement on
https://www.rottentomatoes.com/
If `will-change` is set to a property value where that property could
create a stacking context, then we create a stacking context regardless
of the current value of that property.
We don't yet have a system for "legacy value aliases", but until we have
a lot of them we can handle them manually.
We also have to do this in two places because
parse_css_value_for_property() doesn't call any property-specific
parsing code.
With this, we pass the 8 ref tests in css/selectors/selectors-4/ which
previously failed. This is not technically a full implementation, as we
are supposed to first canonicalize the language range and tag, but that
will require downloading and processing the IANA language subtag
registry:
https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
That's significantly more work, and WPT doesn't seem to test any cases
that require that, so we can leave it for now.
The contain-paint-stacking-context-001a.html test has been removed
for now because it has a 1px tall blue line at the top that should
not be there. With paint containment, this line is removed only in
the actual test case, but not in the reference. This is because of
the font that we use in testing and happens in Chromium as well if
the test is run with that font.
This is implemented by these related changes:
* The Skia alpha type 'Opaque' is selected for surfaces that were
created with the intention of not having an alpha channel.
Previously we were simply creating one with alpha.
* Clearing now happens through Skia's `clear()` which always uses the
source color's value for the result, instead of setting all values
to 0.
* CanvasRenderingContext2D selects a different clearing color based on
the `alpha` context attribute's value.
Previously, the `|=` would not compare strings containing `-`
characters correctly because it would only compare the element
attribute up to the first `-` character.
