Placed worklets implementation behind a pref
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At the moment, worklets are always exposed, even though their spec is still a draft. This PR hides them behind a pref.
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Update WR (text-shadow improvements, iframe + image clips, depth buffer sharing)
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Avoid snapshot handling in animation only restyle
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https://bugzilla.mozilla.org/show_bug.cgi?id=1381431
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Also includes an incidental bugfix for the rendering order of text decorations.
This change depends on servo/webrender#1454 being merged and upstreamed to servo.
In animation-only restyle, we just need to check the element
has animation restyle hints or has recascade self which is a result
of animation-only restyle for ancestors.
has_current_styles() in Servo_ResolveStyle() is intentionally left there,
it will be changed in a subsequent patch.
Implement custom element reactions
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Initial work for implementing custom element reactions: https://html.spec.whatwg.org/multipage/custom-elements.html#custom-element-reactions
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This patch also removes the duplication of style contexts during the
restyle, because otherwise pointer equality of ServoComputedValues stops
holding (and we assert on that in a few places)
Some fixes to selector serialization re: namespaces and universal selector
- Fix eliding default namespace when serializing
- Fix shortest serialization property when namespace prefix is `*|` and there is no default namespace
- Omit universal selector when serializing to match `cssom/serialize-namespaced-type-selectors` (again so we get the shortest serialization)
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I'd like to land #17501 first, because it allows some tests for this to work.
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Don't delete webrender image keys immediately.
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We currently delete webrender image id's immediately on resizing a canvas, which can cause panics. This PR delays deleting the image id until an epoch has passed.
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Stop aborting release builds if we've missed invalidations before calling Servo_ResolveStyle
A lot of people are hitting this in [1]. I think having style (just potentially out-of-date) is less likely to cause weird crashes than failing to style the element entirely, so it's not worth inflicting this level of crashiness on the dogfood population.
[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1381475
If omitting the universal selector in the serialization is possible, we
should do it so we obtain a shorter serialization (to match the behavior
asserted in cssom/serialize-namespaced-type-selectors.html).
For example, if someone writes *|*::before and there is no default
namespace, we should serialize to ::before; however, if there is a
default namespace, we should serialize to *|*::before.
(This is the test case "Universal selector in any namespace followed by
pseudo element).
This matches the behavior implemented by WebKit; that one case in
particular isn't implemented by Gecko, but other cases where the
universal selector should be elided are implemented by Gecko but were not
previously by Servo.
