Implement the forwarded part names step of the CSS Shadow Parts
spec in ShadowRoot::calculate_part_element_map(). When a shadow
host has an exportparts attribute, the inner shadow root's part
element map is consulted and matching parts are added to the
outer shadow root's map under the exported name.
This supports both shorthand same-name forwarding (exportparts=
"foo") and renamed forwarding (exportparts="foo: bar"), and
chains transitively through nested shadow boundaries via
recursive part_element_map() calls.
Fixes 4 WPT tests: simple-forward, simple-forward-shorthand,
double-forward, and precedence-part-vs-part.
:heading() now matches based on a computed heading level, which is based
on the level of the tag (h1, h2, etc) and then modified by these two new
attributes.
I'm caching this heading level on HTMLHeadingElement, based on the dom
tree version. That's more invalidation than is actually needed, but it
saves us calculating it over and over when the document hasn't changed.
The failing test cases are:
- Implicit headingreset for modal dialogs which is apparently unspecced
and controversial.
- Not walking the flat tree properly. A flat tree ancestor of a
slot-assigned element is its slot, which is something we don't do
anywhere that I could find. I've made a note to look into this later.
We also don't implement the `ReflectRange` IDL attribute yet, which
means we're not clamping the read value of `headingOffset`.
Corresponds to:
e774e8e318
Corresponds to part of https://github.com/whatwg/html/pull/9841 and then
https://github.com/whatwg/html/pull/11047
Adding `Auto` as a type state feels a little odd, as it's not an actual
type allowed in HTML. However, it's the default state when the value is
missing or invalid, which works out the same, as long as we never
serialize "auto", which we don't.
We added these methods to propagate OOM errors at process startup, but
we longer fret about these tiny OOM failures. Requiring that these init
methods be called prohibits using these strings in processes that have
not set up a MainThreadVM. So let's just remove them and initialize the
strings in a sane manner.
In doing so, this also standardizes how we initialize strings whose C++
variable name differs from their string value. Instead of special-casing
these strings, we just include their string value in the x-macro list.
In conformance with the requirements of the spec PR at
https://github.com/whatwg/html/pull/9546, this change adds support for
the “switch” attribute for type=checkbox “input” elements — which is
shipping in Safari (since Safari 17.4). This change also implements
support for exposing it to AT users with role=switch.
The popoverTargetElement seems to be one of the only cases of a
reflected Element? attribute in the HTML spec, the behaviour of which
is specified in section 2.6.1.
Buttons can't actually toggle popovers yet because showing/hiding
popovers is not implemented yet.
This one is particularly weird as there's a priority order, and we even
have to look at attributes from the container element if we're inside a
subframe.
Also removing a FIXME about not covering all of the event names as it is
not exactly clear when such a FIXME would be addressed, especially as
these come from multiple specifications.
