Wait as late as possible to assign ClipIds
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This will allow Servo to create ClipScrollNodes later during display
list construction, which will be necessary once rounded rectangles
are removed from the LocalClip structure. Instead of keeping track
of the ClipId of each ClipScrollNode, we keep track of its index in an
array of ClipScrollNodes. This will allow us to access them without a
hash lookup.
Move nsstring from gecko into servo/support/gecko/nsstring
This is the servo side of bug 1403213.
Take 2 of #18941 which got backed out because we botched the landing of the gecko side and I wasn't able to fix it in time.
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Fix the test count in grouping formatter
Now that the WPT update has settled a bit, it seems safe to make sure
that the grouping_formatter properly consumes the data structure
provided.
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Fixed FireMouseEventType mixup
Fix for a bug I didn't catch in #18957. Thanks to @rharel for pointing it out.
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r?@jdm
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Remove XBL as a separate cascading level in Stylo
In Gecko, we handle XBL rules like author rules everywhere, except that XBL rules are added and sorted in an independent step, behave as if it has a separate level.
It is not clear to me why Stylo chose to add a separate level for XBL rules, but it doesn't seem that there is anything special to do with XBL rules.
This bug happens because we don't handle XBL important rules which are handled as part of author rules in Gecko due to lack of the additional level there. We should just follow what Gecko does here and handle them all the same.
(This is the Servo part of [bug 1408811](https://bugzilla.mozilla.org/show_bug.cgi?id=1408811))
In Gecko, we handle XBL rules like author rules everywhere, except that
XBL rules are added and sorted in an independent step, behave as if it
has a separate level.
It is not clear to me why Stylo chose to add a separate level for XBL
rules, but it doesn't seem that there is anything special to do with
XBL rules.
This bug happens because we don't handle XBL important rules which are
handled as part of author rules in Gecko due to lack of the additional
level there. We should just follow what Gecko does here and handle them
all the same.
