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'.
This introduces a basic framework for servo's style system to be able
to query the style of presentation attributes which it can then insert
into the cascade. It uses that framework to implement the size and
color attributes on <font>.
There are a number of improvements that can be done on top of this:
- Implement all other properties
- Abstractify the ruledata parameter of the mappers using templates or virtual dispatch so that it can be a Servo decl block instead
- Implement aforementiond abstraction over Servo decl blocks (this obsoletes the code in the first item above, so it might just be better to skip that and directly do this)
- Replace uses of nsHTMLStyleSheet with an abstract base class containing common elements between Servo and Gecko
I'd prefer for these to be done in separate steps.
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.
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
Urlmageddon
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Still needs a bunch of code in net to be converted in order to get more
advantage of this for images and stuff, but meanwhile this should help quite a
bit with #13778.
Still wanted to get this in.
r? @SimonSapin
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The style system never actually does anything with the document. This allows us
to remove a bunch of stubbing on the Gecko side and streamline some things on
the Servo side in future patches.
This patch introduces infrastructure for the rule tree, and constructs it.
We don't use it yet, nor have good heuristics for GC'ing it, but this should not
happen anymore once we store the rule node reference in the node.
I haven't messed up with memory orders because I want to do a try run with it,
then mess with them.
Take down the ApplicableDeclarationsCache, use the rule tree for doing the cascade.
We also make sure that an element never has an ElementData with ElementDataStyles::Uninitialized,
and eagerly call prepare_for_styling whenever an ElementData is instantiated.
MozReview-Commit-ID: 9YP6eSmdMt0
Instead of maintaining a dummy restyle damage field for text nodes, we can just
perform the necessary parent inheritance and is_changed adjustments on the fly
in ThreadSafeLayoutNode, simplifying the requirements on the style system.
MozReview-Commit-ID: DCqiCRLsLUF