Don't use inherited custom properties for substitution
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Custom properties from parent node has been considered in early stage of cascading them (in [`custom_properties::cascade`](01adcf69d7/components/style/custom_properties.rs (L461-L469))), and there is nothing in the spec stating that substitution should take inherited values into consideration when the value is invalid in the current node. Actually, there is a web-platform test explicitly checks that inherited value is not taken when the value is computed to invalid.
This would fix [bug 1402217](https://bugzilla.mozilla.org/show_bug.cgi?id=1402217).
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This Root<T> relies on the concept of a stable trace object, which doesn't
move for the whole lifetime of the T value. For safety reasons, T must be 'static.
The only implementor of StableTraceObject for now is Dom<T>.
<applet> is not a thing anymore, and that selector in our UA sheet will never
match anyway, since an <applet> element will never have the BROKEN state.
Bug: 1396073
Reviewed-by: xidorn
MozReview-Commit-ID: 7UOMKOv55uJ
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
It's always used from a UA sheet already.
Bug: 1396073
Reviewed-by: xidorn
MozReview-Commit-ID: J3poQuTD1C7
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
We were using the wrong MatchingMode and flags setter just because we didn't
bother threading them down.
This patch fixes the issue seen with the video controls.
MozReview-Commit-ID: Il1WOzRDxI1
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
This could prevent an XBL binding to use some pseudo-elements fairly randomly.
MozReview-Commit-ID: b44DO8qcfD
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>
Devirtualize nsIAtom.
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https://bugzilla.mozilla.org/show_bug.cgi?id=1400459
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Two small tweaks related to MallocSizeOf
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In a later PR, DomRoot<T> will become a type alias of Root<Dom<T>>,
where Root<T> will be able to handle all the things that need to be
rooted that have a stable traceable address that doesn't move for the
whole lifetime of the root. Stay tuned.
I don't want to do such a gratuitous rename, but with all the other types
now having "Dom" as part of their name, and especially with "DomOnceCell",
I feel like the other cell type that we already have should also follow
the convention. That argument loses weight though when we realise there
is still DOMString and other things.
