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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Mach: Add `mach clean-cargo-cache` command
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stylo: Export mozilla::css::ImageValue to stylo.
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This is "Bug 1310885 - Part 0. (gecko) Export mozilla::css::ImageValue to stylo."
We need to land it separately to prevent build break.
Link to the gecko bug:
https://bugzilla.mozilla.org/show_bug.cgi?id=1310885.
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Enable subpixel anti-aliasing on text by default.
No doubt there are still some bugs and missing features related to subpixel text anti-aliasing.
But enabling by default should allow us to detect these and fix them.
If we run into any major issues, this is a standalone commit that can be reverted while we fix the problem.
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No doubt there are still some bugs and missing features related to subpixel text anti-aliasing.
But enabling by default should allow us to detect these and fix them.
If we run into any major issues, this is a standalone commit that can be reverted while we fix the problem.
Remove obsolete paint threads option #16716
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Remove paint_threads from `ports/cef/core.rs` and `components/config/opts.rs`
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Improvements to gradients.
This is a collection of commits improving the rendering of linear and radial gradients by making them conform more closely to the spec.
All commits are are independent and should work without the others.
These commits address the following issues:
* a956e3fd52resolves#3908 but contains also some other necessary changes to `convert_gradient_stops`. The updated function has a few more copys but should be more correct. Maybe @pcwalton wants to comment since he has originally written the code.
* b230be8aaf partially solves #16638. (Partially because `border-image-outset` is not implemented. This is an older issue for border gradients: #15894.
To quickly catch regressions and see changes to gradients I have created [a set of twelve manual testcases](https://pyfisch.org/stuff/testcases-gradients.html) and placed them in a single file. Attached are two files. One shows how the gradients were rendered before the PR the other one with the changes applied.


r? @emilio
and maybe also @jdm?
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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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If the first stop of a non-repeating gradient is
not placed at offset 0.0 it is duplicated at this
position. This solves the problem of the first
stop being ignored if it is placed at the same
offset as the next stop.