Implement an ExtremumLength type which contains all the enumerated
keyword values for min-width, min-height, max-width, and
max-height. Then, implement a MinLength which can be used for min-width
and min-height. So far this just maps to Gecko values.
Refs #13821.
Fix parsing methods of column-{gap,width}
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They weren't accepting {normal, auto} keywords. Fixed parsing methods of these properties.
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- [X] These changes fix#15088 (github issue number if applicable).
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Add gecko glue for perspective/transform properties
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To be able to add glue for these properties, we needed to change their structs. They are moved from effects to box and added stylo glue.
This PR covers these properties:
- perspective
- perspective-origin
- backface-visibility
- transform-box
- transform-style
- transform-origin
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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 they are stylo changes
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