Fix stylo bindings for Gecko changes to nsITheme constants in bug 1367577
These changes fix the stylo bindings for the changes to the Gecko nsITheme constants in [bug 1367577](https://bugzilla.mozilla.org/show_bug.cgi?id=1367577).
I believe there isn't anything in these changes that should affect the stylo build (as opposed to the servo build, which I've tested on try in that bug).
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This is a little bit odd, because I didn't want to do all the work to
convert the theme constants to an enum class (although that would be
nice to do in the future). So this makes them a regular enum, but still
uses gecko_constant_prefix rather than gecko_enum_prefix because that
makes it possible to add the NS_THEME_ prefix that's still present.
mathvariant attributes should affect computed font style and weight in stylo
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- [X] These changes fix https://bugzilla.mozilla.org/show_bug.cgi?id=1367301
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- [X] These changes do not require tests because this is stylo-only and Gecko tests it.
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Speed up the visited cascade by only running it for the properties that are
actually visited dependent. (These are only the properties where the separate
set of visited styles is even read at all, so running the rest is wasted work.)
MozReview-Commit-ID: 5B7wYtuH974
To support visited styles, we match and cascade a separate set of styles any
time we notice that an element has a relevant link.
The visited rules and values are held in `ComputedStyle` alongside the
regular rules and values, which simplifies supporting various APIs like
`cascade_primary_and_pseudos` which expect easy access to previously matched
rules.
To simplify passing the additional values around, an additional reference to the
visited `ComputedValues` is placed inside the regular `ComputedValues`.
MozReview-Commit-ID: 2ebbjcfkfWf
Don't use mem::transmute in from_gecko-weight
Fixes#16966.
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it's a minor refactor
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Background shorthand parsing issues
Two issues around background shorthand:
1. color should be only allowed in the last element of background shorthand
2. text should not be allowed in background shorthand
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Although there are no specific tests for this yet if any code does try
to perform addition or accumulation with a font-stretch value it will
likely fail the bounds check in the Into trait. To avoid that this
patch provides an basic implementation of add_weighted for font-stretch
that should work correctly with portions whose sum is outside the [0.0,
1.0] range.
Fix stylo's text-overflow handling to match gecko.
A single value sets the text-overflow on the _end_ of the text, not both start and end.
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The 'contain' property can affect whether a box is a fixed-pos containing block
This makes will-change:contain work correctly.
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