Mutation Observer API
Rebased from #16668.
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- [X] These changes fix (partially) #6633
- [X] There are tests for these changes
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In a similar way to Position, now specified and computed gradients share
a common Gradient type defined in style::values::generics::image.
This allows us to reuse most code for many style traits like ToCss,
HasViewportPercentage and ToComputedValue.
The test changes are the fallout of the disappearance of AngleOrCorner::None,
which align our code to the spec for serialisation, where components that can
be omitted should be omitted.
We need another flag that represents allow-negative-number for SMIL, so
this enum will also comprise the another parsing mode that allows negative number.
Disallow negative duration for animation and transition
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- [X] These changes fix#15343
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- [X] There are tests for these changes written by @simon-whitehead . Thank you!
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Fix unsafe AtomicRefCell<T> transmutes in Layout component
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Fixes unsafe transmute between `AtomicRefCell<PersistentLayoutData>` and `AtomicRefCell<PartialPersistentLayoutData>` which have different memory alignment in 32 bit archs leading to SEGV crashes. See https://github.com/servo/servo/issues/16817 and https://github.com/servo/servo/pull/16816
mem::align_of values in 32 bit archs (e.g. Android):
```
PersistentLayoutData 8
PersistentLayoutData 4
AtomicRefCell<PersistentLayoutData> 8
AtomicRefCell<PartialPersistentLayoutData> 4
```
mem::align_of values in 64 bit archs
```
PersistentLayoutData 8
PersistentLayoutData 8
AtomicRefCell<PersistentLayoutData> 8
AtomicRefCell<PartialPersistentLayoutData> 8
```
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style: Slim down SharedStyleContext, and do various other cleanups around the style crate.
This slims down SharedStyleContext, in preparation for a few things.
First, I would like to eventually move the stylist to the document in Servo, in
order for it to hold the StyleSheetSet.
Also, this gets rid of a fair amount of overhead while creating it in stylo.
Fixes bug 1363245.
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A specified position is now a struct made of two values of different types,
the first one being PositionComponent<X>, and the second one PositionComponent<Y>.
A position component is represented by the new enum PositionComponent<Side>,
with the three values Center, Length(LengthOrPercentage), and
Side(Side, Option<LengthOrPercentage>).
Side keywords are represented by the X and Y enums, which don't include a value
for the center keyword anymore. They are accompanied by the Side trait, which
allows us to determine whether a side keyword is "left" or "top".
This refactor simplified the parsing and serialisation code and exposed bugs in it,
where it would reject valid <position> values followed by arbitrary tokens,
and where it would fail to prefer "left" to "right" when serialising positions
in basic shapes.
bump required rayon version to 0.7
...and bring jpeg-decoder along for the ride. Minor tweaks were necessary because of rayon API changes.
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