The `cascade_primary_or_pseudo` function was nice when we shared more code, but
right now I think it just makes it harder to understand what's going on.
Fix typo and simplify for PresentationalHintsSynthesizer
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I've chosen this approach mainly because there's no other good way to guarantee
the model is correct than holding the snapshots alive until a style refresh.
What I tried before this (storing them in a sort of "immutable element data") is
a pain, since we call into style from the frame constructor and other content
notifications, which makes keeping track of which snapshots should be cleared an
which shouldn't an insane task.
Ideally we'd have a single entry-point for style, but that's not the case right
now, and changing that requires pretty non-trivial changes to the frame
constructor.
MozReview-Commit-ID: FF1KWZv2iBM
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
1. We add a new arm to TransitionProperty, TransitionProperty::Unsupported,
which contains an Atom, so it's better to remove the Copy trait from
TransitionProperty.
2. TransitionProperty::Unsupported(Atom) represents any non-animatable, custom,
or unrecognized property, and we use Atom to store the ident string for
serialization.
1. We need to call get_after_change_style, which is the computed styles
without transition rules, while process_animations.
2. If we have after-change style, we may replace the new computed values with
after-change style, according to whether we really need to update
transitions.
3. There are some cases we don't update transitions, so we need to early
return. might_needs_transitions_update() will check it first and it
will filter out most common cases.
4. needs_transitions_update() will check each property and existing running
transitions to make sure we really don't need to update transitions.
The logic of this function is similar with that of
nsTransitionManager::DoUpdateTransitions().
MozReview-Commit-ID: 2ccdPjgrxKz
Add one FFI to check if there is any transition in CSSTransitionCollection.
This will be used to check if we need to update transition and if we
should compute the after-change style.
MozReview-Commit-ID: 6HpVAtrx6Rc
While we're at it, we also eliminate the 'unknown' dom depth for the
bloom filter. Computing depth has negligible cost relative to the
amount of work we do setting up the bloom filter at a given depth.
Doing it once per traversal should be totally fine.
I originally separated the elimination of unknown dom depth from the
traversal changes, but I got bloom filter crashes on the intermediate
patch, presumably because I didn't properly fix the sequential traversal
for this case. Given that the final state is green, I just decided to
squash and move on.
The UpdateAnimationsTasks is a bitflags and each bit is generated from
Gecko's UpdateAnimationsTasks (enum class) values for matching values
between C++ and Rust. For this reason, the bitflags is annotated as
(feature = "gecko"), as a result update_animations() which uses this bitflags
also became gecko-only function.
We will set the flag when the root node of the traversal has
has-animation-only-dirty-descendants flag or has animation restyle hints.
Also we will use this flag to detect whether we need to trigger CSS transitions
or not.
If an element has only CSS animations we don't need to get transition rule,
and vice versa. This will be used when we implement eRestyle_CSSAnimations
and eRestyle_CSSTransitions.
We create the SequentialTask only if:
* We have no old computed values and we have animation name style in the new
computed values.
* Any animation properties is changed.
* display property is changed from 'none' and we have animation name style.
* display property is changed to 'none'.
In a subsequent patch we skip the SequentialTask if we have no running
animations and the display propery is changed to 'none'.
We use TElement::get_animation_rule to get the animation rules from
Gecko side, which contain the interpolated values of the specific
element and the pseudo type.
Sometimes Gecko eagerly styles things without processing pending restyles first. In
general we'd like to avoid this, but there can be good reasons (for example, needing
to construct a frame for some small piece of newly-added content in order to do something
specific with that frame, but not wanting to flush all of layout). Just handle it.
MozReview-Commit-ID: EjXs0M4855Q
The primary idea of this patch is to ditch the rigid enum of Previous/Current
styles, and replace it with a series of indicators for the various types of
work that needs to be performed (expanding snapshots, rematching, recascading,
and damage processing). This loses us a little bit of sanity checking (since
the up-to-date-ness of our style is no longer baked into the type system), but
gives us a lot more flexibility that we'll need going forward (especially when
we separate matching from cascading). We also eliminate get_styling_mode in
favor of a method on the traversal.
This patch does a few other things as ridealongs:
* Temporarily eliminates the handling for transfering ownership of styles to the
frame. We'll need this again at some point, but for now it's causing too much
complexity for a half-implemented feature.
* Ditches TRestyleDamage, which is no longer necessary post-crate-merge, and is
a constant source of compilation failures from either needing to be imported
or being unnecessarily imported (which varies between gecko and servo).
* Expands Snapshots for the traversal root, which was missing before.
* Fixes up the skip_root stuff to avoid visiting the skipped root.
* Unifies parallel traversal and avoids spawning for a single work item.
* Adds an explicit pre_traverse step do any pre-processing and determine whether
we need to traverse at all.
MozReview-Commit-ID: IKhLAkAigXE
