Make emtpy rule can be inserted into rule tree
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We really want to ensure empty rule nodes appear in the rule tree for devtools, this condition ensures that if we find an empty rule node, we insert it at the normal level.
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Bindgen bitfield enums don't work as return values with the Linux 32-bit ABI at
the moment because they wrap the value in a struct.
This causes the Rust side to believe the callee expects space for the struct
return value, while C++ believes it's just an integer value.
MozReview-Commit-ID: FRBqlZuMiAR
Update Firefox version in user agent
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GitHub has started throwing warnings about using an outdated version of Firefox when loaded with Servo. I am assuming that this is due to Servo using Firefox 37.0 in its user agent which was set in 2015 and hasn't been updated since then. I don't know if updating this should cause any site compatibility issues or not.
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Make content animatable
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cleanup embedder/compositor/constellation/script messages
Fix: #17226#17200#17201
This is work in progress. Some tests still fail.
I'd like to get early feedback as it's a pretty large PR.
There is nothing fundamentally new. Basically, I added TopLevelBrowsingContrextId to the relevant messages between the embedder, the compositor and the constellation, and enforced the PipelineId to be attached to each ScriptMsg (see #17201).
I unaliased all the ScriptMsg. It was getting difficult to understand the nature of the message as ScriptMsg was used aliased CompositorMsg sometimes (CompositorMsg is an actually type of message already). I renamed constellation_chan to script_to_constellation_chan, again, for clarification.
This cleanup code is necessary for #15934 and for tabs support.
/cc @asajeffrey can I ask you to look at this? No need for a formal review, I need feedback at this stage.
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Don't convert zero component value to 'auto' in clone__moz_image_region.
Currently Gecko treats 'auto' component value as zero for animation.
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https://bugzilla.mozilla.org/show_bug.cgi?id=1387951
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For CSS Transitions we want this case to return Err() so we know that the two
values are not interpolable.
For CSS Animations/Web Animations we implement discrete animation as the
fallback behavior when Err() is returned.
column-count should be greater than or equal to 1. Also it should be less than
or equal to nsStyleColumn_kMaxColumnCount since we limit it in
set_column_count().
Make scroll-snap-{coordinate, destination} discrete animation.
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https://bugzilla.mozilla.org/show_bug.cgi?id=1387941
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Make -moz-appearance animatable
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We convert a perspective function into a ComputedMatrix, but we apply the
perspective length to a wrong matrix item. We should put it into m34,
instead of m43. m43 is for translate parameter Z.
