Handle 3- and 4- valued <position>s in style
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This is first part of fix#12690 and covers just specified style part for now.
r? @Manishearth
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12902 typedefs
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Using type alias instead of newtype.
Removing duplicated implementation, it's already inherited.
No more type constructors and foo.0
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Merge normal and important declarations in style rules
Have a single Vec instead of two. Fix#3426
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Update selectors to 0.10, with ToCss serialization.
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r? @emilio
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10933/shorthands
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This implements the serialization of nearly all of the css shorthand properties with the following exceptions:
1. font - this may be implemented correctly, but I am not 100% sure
2. border-radius - I do not know how to implement this, since I am not familiar with how the property works
3. background - this is implemented, but I think that the implementation might be a tiny bit off.
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Fix restyling on viewport resize.
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Fixes https://github.com/servo/servo/issues/12835
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Support 'word-spacing' for geckolib
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