Set the flag of the fragment of children in a flex container according
to the direction of the container. The mark is done on the fragment
because flex item enstablish a stacking context when its z-index is
non-zero ,despite its `position' property.
This creates a sharp distinction between `Arc<Flow>`s, which may be
owned by anyone, and `FlowRef`s, which may only be owned by the
traversal code. By checking the reference count, we ensure that a `Flow`
cannot be pointed to by `Arc`s and `FlowRef`s simultaneously.
This is not a complete fix for #6503, though it is a necessary start
(enforcing the no-aliasing rule of `FlowRef::deref_mut` will require far
more work).
Fixes#14014
This patch introduces a "legalizer", which encapsulates all the
anonymous flow generation logic in one place. The legalizer knows how
to, for example, place adjacent blocks with `display: table-cell` in the
same table row.
Improves etsy.com.
Closes#13782.
10.8, and implement `vertical-align: middle` per CSS 2.1 § 10.8.1.
`InlineMetrics` has been split into `InlineMetrics` for fragments and
`LineMetrics` for lines. Both structures' fields have been renamed in
order to more clearly delineate the difference between *space* and
*content*. Vertical positioning of fragments has been reworked to take
margins and borders into account only for replaced content.
This patch fixes the `vertical_align_super_a.html` reftest. Servo now
matches the rendering that Gecko and WebKit produce.
Additionally, this includes a test for the popular inline-block
centering technique described here:
https://s.codepen.io/shshaw/fullpage/gEiDt?#Inline-Block
We don't need this for Gecko, and it's hard to implement in that case because
there's nowhere obvious to put it (we don't plan to create TSDs for non-dirty
nodes, and non-dirty nodes can have dirty children which require the
children_to_process atomic). There are various solutions here, but punting is
the easiest.
We'll need to rethink this if/when we need to do a bottom-up traversal for
Gecko.
It's not possible to implement a Ref::map equivalent method on AtomicRefCell
while having AtomicRefCell implemented on top of RwArc. We could potentially
reimplement AtomicRefCell to be more like RefCell and add a Ref::map equivalent
method, but I (and pcwalton) think we should try just cloning a few extra
Arcs at these callsites instead.
MozReview-Commit-ID: 6H8vAWguO3z
Because this is a bottom-up traversal it can generates flows and throw them away. To prevent that, this cascades an internal `-servo-under-display-none` property and then checks that during flow construction. Fixes#1536.
