MallocSizeOf is similar to the existing HeapSizeOf trait from the
heapsize crate. The only difference is that MallocSizeOf's
malloc_size_of_children() function takes an additional MallocSizeOfFn
argument, which is used to measure heap blocks. This extra argument
makes MallocSizeOf match how Gecko's memory measurements work, and is
required for Stylo to integrate with DMD.
The patch also introduces a second trait, MallocSizeOfWithGuard, which
is much the same as MallocSizeOf, but with a |guard| argument for the
global style lock.
Finally, the patch uses the new traits to measure a small amount of
Stylo's memory usage.
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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It seems that changeset 97ce9ed5b0
mistakenly changed the check that a cascade level to keep is *not* an
animation level to a check that it *is* an animation level.
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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Stylo: Deep clone ServoStyleSheets.
MozReview-Commit-ID: 6hYIcOa86Y
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https://bugzilla.mozilla.org/show_bug.cgi?id=1339629https://reviewboard.mozilla.org/r/135314/
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- [ ] These changes fix #__ (github issue number if applicable).
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