Implement matchMedia and MediaQueryList
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Fixes#13376.
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Fold some DisplayList methods into DisplayListBuildState
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This makes the API used to build display lists quite a bit simpler and
reduces the amount of auxiliary data structures that need to be passed
around. It is also important preparation work for separating scrolling
areas from stacking contexts.
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Parsing/Serialization for scroll-snap-points-*
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Implements Parsing/Serialization for scroll-snap-points-x and scroll-snap-points-y
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This matches the previous default (network.mime.sniff off) behaviour in all
but one case: we will now accept a font without a `Content-Type` header, which
would previously have been ignored.
This makes the API used to build display lists quite a bit simpler and
reduces the amount of auxiliary data structures that need to be passed
around. It is also important preparation work for separating scrolling
areas from stacking contexts.
Make style::context use parking_lot::RwLock
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The main motivation is to use `parking_lot::RwLock` instead of `sync::RwLock` in `style::context`, so that we can make `Stylesheet` be hold in a `parking_lot::RwLock` like other structs used for geckolib.
r? @SimonSapin
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We also make sure that an element never has an ElementData with ElementDataStyles::Uninitialized,
and eagerly call prepare_for_styling whenever an ElementData is instantiated.
MozReview-Commit-ID: 9YP6eSmdMt0
Make test-tidy check for alphabetical ordering of #![feature(...)] statements
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