Remove unnecessary try!'s
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These try!'s are unnecessary here. We can remove them.
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- [X] `./mach test-tidy` does not report any errors
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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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- [X] These changes do not require tests because it's for stylo.
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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] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [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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- [ ] These changes do not require tests because _____
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