Remove unnecessary try!'s
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These try!'s are unnecessary here. We can remove them.
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- [X] These changes do not require tests because it's just refactoring
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Stylo: Store animation properties into gecko's struct
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This is the counter part of https://bugzilla.mozilla.org/show_bug.cgi?id=1328786
All patches get reviewed by r=@heycam.
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Correctly handle unserializable shorthand
get_shorthand_appendable_value doesn't always return a serializable value. This change makes it handle that case correctly.
This change also updates step number in property_value_to_css to reflect the latest spec.
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- [x] These changes fix stylo [bug 1329533](https://bugzilla.mozilla.org/show_bug.cgi?id=1329533)
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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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Fix serialization of timing-function
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`transition-timing-function` and `animation-timing-function` properties corrected to reflect [the spec](https://drafts.csswg.org/css-transitions/#serializing-a-timing-function). It was converting function keywords to `cubic-bezier` or `steps` functions directly. But we needed to store it to use in the serialization step.
---
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- [X] These changes fix#14822 (github issue number if applicable).
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Allow sharing non-common style affecting attribute selectors.
Something I just noticed while re-reading that code is that we prevent sharing among siblings with different non-common attributes, even though we already have the infra to match those selectors:
```rust
if !match_same_not_common_style_affecting_attributes_rules(element,
candidate_element,
shared_context) {
miss!(NonCommonAttrRules)
}
```
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Support property aliases
Aliases now get forwarded to their "original" property name at parse time. CSSOM continues to provide access through alias getters.
We'll need to probably add `${"-webkit-foo -moz-foo" if gecko else ""}` all over the place. Might want to come up with a convenient attibute name for that (`gecko_prefix="mw"`) or something.
r? @heycam or @bholley
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