Preserve units in computed Angle
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It was converting all angles to radians before. But other browsers preserves the angle units. Fixed that behavior.
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- [X] These changes fix#16594 and [Bug 1360659](https://bugzilla.mozilla.org/show_bug.cgi?id=1360659)
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Reverse Number and LengthOrPercentage in LengthOrPercentageOrNumber
"0" must be parsed as the number 0, not the unitless 0px length.
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Implement radial gradients
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This PR passes the `radial-gradient` function down from CSS parsed properties to webrender. It currently lacks tests but the examples from MDN and some other tests work fine. Probably there are some wpt tests I can enable?
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- [x] These changes fix#11779 (github issue number if applicable).
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Move impl's into macro for macro-generated keyword types
Three keyword types are created through a macro but have some of their
impl's handled elsewhere. Since all impl's are the same, this commit
moves them into the macro to have them auto generated, for more concise
code.
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Three keyword types are created through a macro but have some of their
impl's handled elsewhere. Since all impl's are the same, this commit
moves them into the macro to have them auto generated, for more concise
code.
Add calc method for CalcLengthOrPercentage
* Add calc method to calculate formula value with parent size
* Add unit test case
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Please see this issue: https://github.com/servo/servo/issues/15986
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* Add to_computed method to calculate `calc()` value with parent size,
if parent container size is `None`, the result will be `None`.
* Add from_option method for `MaybeAuto`, to construct from
`Option<Au>`.
* Update some test case.
