stylo: Export RefPtr<ImageValue> to stylo.
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This is the second patch in bug 1310885
"Bug 1310885 - Part 2. (stylo) Export RefPtr<ImageValue> from gecko to stylo."
Bugzilla link:
https://bugzilla.mozilla.org/show_bug.cgi?id=1310885
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register stylo threads with the gecko profiler
Now that we require rayon 0.7, we can register start and stop handlers
that take care of dealing with the Gecko profiler for rayon threads in
the style thread pool.
Manually verified that adding "StyleThread" to the list of threads tracked by the Gecko profiler addon caused lots of threads to show up in a profile, and all the stack unwinding goodness seems to work!
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Now that we require rayon 0.7, we can register start and stop handlers
that take care of dealing with the Gecko profiler for rayon threads in
the style thread pool.
Add comments to shorthand alias logic that explains the interesting bahavior
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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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Fix variable serialization bug on shorthand alias properties
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-moz-transform were having a problem with variable serialization. It wasn't printing transform's value and transform wasn't printing -moz-transform's if their value was a variable. This PR fixes that.
Reduces stylo -moz-transform failures to 2: https://treeherder.mozilla.org/#/jobs?repo=try&revision=3fd3a57873e5e98dfcb173eef4b13822a66fdf6a
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Generate atom files at build-time
The commits here basically do the following things:
1. move all generated files for gecko into "gecko/generated" so that we can copy all of them around
2. make regen_atoms.py generate file to the out dir rather than in-tree
3. make the build script invoke regen_atoms.py when bindgen feature is enabled
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Fix parsing behavior of text-shadow property
Blur radius should reject negative values. There was already `Shadow` struct for properties like this. `filter: drop-shadow` also has the same syntax with that property. I thought sharing the same code would be better and used Shadow struct for parsing. Converted to SpecifiedTextShadow to get rid of unneccessary fields and to be able to convert its computed value. Maybe it would be better to avoid using `Shadow` or just using `Shadow` but sharing code and avoiding unneccessary fields seems better.
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