Prefer Either type for LengthOrNumber
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This adds `impl GeckoStyleCoordConvertible for Either<A, B>` and makes `LengthOrNumber` prefer `Either<A, B>`.
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r? @SimonSapin
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This commit itself only moves things around and adds an extra parameter to the
`apply_declarations` function to eventually handle #14079 correctly.
Probably needs a more granular API to query fonts, á la nsFontMetrics, but
that's trivial to do once this is landed.
Then we should make the font provider mandatory, and implement the missing stylo
bits.
This patch introduces infrastructure for the rule tree, and constructs it.
We don't use it yet, nor have good heuristics for GC'ing it, but this should not
happen anymore once we store the rule node reference in the node.
I haven't messed up with memory orders because I want to do a try run with it,
then mess with them.
Take down the ApplicableDeclarationsCache, use the rule tree for doing the cascade.
Use enum BorderWidth instead of a tuple-like struct to store the specified
value. BorderWidth is needed to be used in both longhand and shorthand
border width properties, so I put it in `specified` module.
Fixed#13869.
Fix radial gradient's <size>/<ending-shape> parsing
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Parsing now handles sizes and shapes in various order.
I had to delete `EndingShape`'s parse implementation and mix it with `Position` in `parse_radial`. It became a bit complicated to read but I couldn't make it simpler.
r? @Manishearth
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style: Don't incorrectly clamp values in calc that might not be only lengths.
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Expressions with percentages may be negative or positive at computed value time.
So, we can only clamp lengths at computed value time, which is what the other
browsers do.
Handle specialized serialization of <position> in basic shapes
Fixes#13083
We temporarily broke basic-shape serialization in #13042 when 4-value positions were implemented, since I didn't want to increase the scope of that PR too much.
This fixes it.
r? @SimonSapin
cc @canaltinova
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Prefer length and percentage for word spacing
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The goal is to make use of `LengthOrPercentage` for word spacing in `ShapingOptions`, but since it makes use of `f32` which doesn't implement `Hash`, we're going for `NotNan<f32>` from [ordered-float](https://github.com/reem/rust-ordered-float/), which supports hashing. Instead of implementing `Hash` for `LengthOrPercentage` and thereby the inner types like `CSSFloat`, `CalcLengthOrPercentage`, etc., we convert it to `(Au, NotNan<f32>)`.
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