This commit also removes the old restyle_hints module and splits it into
multiple modules under components/style/invalidation/element/.
The basic approach is to walk down the tree using compound selectors as needed,
in order to do as little selector-matching as possible.
Bug: 1368240
MozReview-Commit-ID: 2YO8fKFygZI
Stylist accessors
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Add accessor methods for the `device` and `ruleset` fields in the `Stylist` struct.
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- [X] These changes fix#16857 (github issue number if applicable).
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This slims down SharedStyleContext, in preparation for a few things.
First, I would like to eventually move the stylist to the document in Servo, in
order for it to hold the StyleSheetSet.
Also, this gets rid of a fair amount of overhead while creating it in stylo.
Fixes bug 1363245.
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 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
I wanted to add an environmental variable to disable the style sharing
cache for gecko, but the current pattern involves lazy_static!, which
involves an atomic operation on lookup, which is a bit hot to do each
time we try to share styles. This makes that work happen once per
process.
The current mechanism requires threading a lot of this state through a bunch of
callsites that are several layers of abstraction above the code that actually
uses this vector (which is only compiled for servo). Putting it in
CurrentElementInfo gets it nicely out of the way.
MozReview-Commit-ID: 9PLBKcJreN0
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.
Now that cascade() gets a Device, we can use the default computed values from
there to avoid propagating that state all over the place.
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
At least until we support scrollbars properly, this size is going to be the
correct one. I've left a TODO to grab the proper one once we support it.
This allows to trivially test viewport units for now.
MozReview-Commit-ID: JdaZ6WlZ2C6
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
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'.
