Replace all uses of the style::stylearc alias with servo_arc.
The `stylearc` alias is left there temporarilly and will be removed completely in a later commit/PR where also `components/style/gecko/generated/structs_{debug|release}.rs` are re-generated (they still use the old alias).
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- [X] These changes fix#17768 (github issue number if applicable).
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The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
stylo: Bug 1335998 - Handle interpolation and accumulation of mismatched transform lists
These are the interdependent patches of Bug 1335998. We want to do interpolation and accumulation for mismatched transform lists, so introduce ComputedOperation::InterpolateMatrix and ComputedOperation::Accumulation. Both arms store the from_list and to_list, and resolve them until we have the layout information. For the Servo part, we haven't implemented how to read the transform lists in layout/fragment.rs, but I think it would be easy. (related issue #13267)
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [Bug 1335998](https://bugzilla.mozilla.org/show_bug.cgi?id=1335998)
- [X] There are tests for these changes
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We convert ComputedOperation::{Accumulate, Interpolate}Matrix into gecko type
not on the main thread, so we cannot use nsCSSValueList_heap (which is not
thread safe so we cannot create it and destroy it on different threads).
Therefore, we use nsCSSValueSharedList to represent the cloned
from_list/to_list. In this patch, we also implement the reversing way,
i.e. Convert eCSSKeyword_{accumulate, interpolate}matrix into
{Accumulate, Interpolate}Matrix.
