Fix animation shorthand parsing
which is somehow broken after #15779.
But it seems there are various issue around the animation shorthand parsing, so I try to fix it to make it match the spec.
I expect this change to fix most parsing failures in Gecko's test suite, although I haven't tested.
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Shorthand cannot represent CSS-wide keyword in individual longhands, and
thus we cannot serialize longhand with CSS-wide keyword as part of a
shorthand.
fix {transform,perspective}-origin accepts (and ignores) anything for…
… their second part of value
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Background serialization of multiple values.
Similar to animation, the serialization of multiple backgrounds should
return the longhands serialization if there are an unequal number of
values for the required properties. This is part of #15398
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Update cssparser to 0.11
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<s>Depends on https://github.com/servo/rust-cssparser/pull/122.</s>
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Similar to animations and backgrounds, multiple transitions should be
serialized as a list of shorthand values only if the number of values
for each longhand property is the same. Otherwise we default to the
longhand serialization. Fixes#15398
The match_ignore_ascii_case! macro does ASCII-case-insensitive matching.
In cssparser verion 0.11, it will require its patterns to be already
lower case.
