Pretty much the same setup we have for document.
We have the awkwardness of having to check containing shadow manually for
ShadowRoot because it's not available in TNode (and making it available added a
bit more complexity that wasn't worth it IMO).
Bug: 1464428
Reviewed-by: xidorn
MozReview-Commit-ID: CqOh0sLHf6o
This also adopts the resolution of [1] while at it, and switches XUL to not
support display: contents until a use case appears.
This makes our behavior consistent both with the spec and also in terms of
handling dynamic changes to stuff that would otherwise get suppressed.
Also makes us consistent with both Blink and WebKit in terms of computed style.
We were the only ones respecting "behaves as display: none" without actually
computing to display: none. Will file a spec issue to get that changed.
It also makes us match Blink and WebKit in terms of respecting display: contents
before other suppressions, see the reftest which I didn't write as a WPT
(because there's no spec supporting neither that or the opposite of what we do),
where a <g> element respects display: contents even though if it had any other
kind of display value we'd suppress the frame for it and all the descendants
since it's an SVG element in a non-SVG subtree.
Also, this removes the page-break bit from the display: contents loop, which I
think is harmless.
As long as the tests under style are based in namespace id / node name /
traversal parent, this should not make style sharing go wrong in any way, since
that's the first style sharing check we do at [2].
The general idea under this change is making all nodes with computed style of
display: contents actually honor it. Otherwise there's no way of making the
setup sound except re-introducing something similar to all the state tracking
removed in bug 1303605.
[1]: https://github.com/w3c/csswg-drafts/issues/2167
[2]: https://searchfox.org/mozilla-central/rev/fca4426325624fecbd493c31389721513fc49fef/servo/components/style/sharing/mod.rs#700
Bug: 1453702
Reviewed-by: mats, xidorn
MozReview-Commit-ID: JoCKnGYEleD
This adds TShadowRoot to the `dom` module.
Right now it barely adds uses of it, but this is a prerequisite to fix a bunch
of Shadow DOM bugs and separate it from the XBL mess.
The key here is that we only filter longhands if the shorthand is accessible to
content and vice-versa. This prevents the bug that prevented me to land this
patch before, which was us not expanding properly chrome-only shorthands.
Again, this is incomplete, and I need to teach LonghandsToSerialize to get a
potentially incomplete list of properties, and all that.
More improvements to come. In particular, this still iterates through Shadow DOM
in each_xbl_cascade_data, but that should be changed later. That allows to
cleanup a bunch of stuff and finally fix Shadow DOM cascade order.
We still rely on the binding parent to be setup properly in the shadow tree, but
that requirement can go away later (we can walk the containing shadow chain
instead).
This mostly focuses on removing the XBL binding from the Shadow host.
It'd be nice to do EnumerateShadowRoots faster. I think that should also be a
followup, if needed.
Bug: 1425759
Reviewed-by: xidorn
MozReview-Commit-ID: Jf2iGvLC5de
We are relying in the XBL binding for the shadow host, we need to check
explicitly.
Also, we were checking in_shadow_tree, which is really broad. Just
is_html_slot_element should do, since the rest of the nodes should have only
light tree children.
Bug: 1425759
Reviewed-by: xidorn
MozReview-Commit-ID: KAFRVxaLsK
It's just a struct aggregating stylesheets + CascadeData, with a quirks_mode
parameter because XBL sucks so bad.
Bug: 1436059
Reviewed-by: xidorn
MozReview-Commit-ID: 7q99tSNXo0K
Now that we have an Element around on cascade, we can stop using the cascade
flags mechanism to pass various element-related state, like "is this element the
root", or "should it use the item-based display fixup".
That fixes handwaviness in the handling of those flags from style reparenting,
and code duplication to handle tricky stuff like :visited.
There are a number of other changes that are worth noticing:
* skip_root_and_item_based_display_fixup is renamed to skip_item_display_fixup:
TElement::is_root() already implies being the document element, which by
definition is not native anonymous and not a pseudo-element.
Thus, you never get fixed-up if your NAC or a pseudo, which is what the code
tried to avoid, so the only fixup with a point is the item one, which is
necessary.
* The pseudo-element probing code was refactored to return early a
Option::<CascadeInputs>::None, which is nicer than what it was doing.
* The visited_links_enabled check has moved to selector-matching time. The rest
of the checks aren't based on whether the element is a link, or are properly
guarded by parent_style.visited_style().is_some() or visited_rules.is_some().
Thus you can transitively infer that no element will end up with a :visited
style, not even from style reparenting.
Anyway, the underlying reason why I want the element in StyleAdjuster is because
we're going to implement an adjustment in there depending on the tag of the
element (converting display: contents to display: none depending on the tag), so
computing that information eagerly, including a hash lookup, wouldn't be nice.
