Fix scroll root of absolutely positioned elements
Absolutely positioned elements should be given the scroll root of their
containing block and not necessarily the scroll root of their parent.
This fixes several CSS tests, though others are still failing pending a
similar fix for inherited clipping rectangles.
Fixes#13530.
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The UpdateAnimationsTasks is a bitflags and each bit is generated from
Gecko's UpdateAnimationsTasks (enum class) values for matching values
between C++ and Rust. For this reason, the bitflags is annotated as
(feature = "gecko"), as a result update_animations() which uses this bitflags
also became gecko-only function.
Absolutely positioned elements should be given the scroll root of their
containing block and not necessarily the scroll root of their parent.
This fixes several CSS tests, though others are still failing pending a
similar fix for inherited clipping rectangles.
Fixes#13530.
Animation only restyles
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This is a PR of https://bugzilla.mozilla.org/show_bug.cgi?id=1344966
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style: Add <keyword>::from_ident helper to avoid tokenizing the same value multiple times.
We can use this to avoid tokenizing multiple times in some places, like #16127.
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to_css of counter-increment returns none when there are no properties.
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Changed to_css in style::properties::longhands::counter_increment returns "none" if there are no properties defined.
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- [X] These changes fix#15977 (github issue number if applicable).
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All traversal processes are like this:
1. Traverse only elements that have this restyle hint (animation-only traversal)
RESTYLE_CSS_ANIMATIONS is stripped off from restyle hints of the elements
2. Traverse all dirty elements (normal traversal)
3. Create a SequentialTask if we have updated CSS Animations properties in
the normal traversal
4. Traverse elements that need to have updated animation style as a result of 3
(second animation-only traversal)
We will set the flag when the root node of the traversal has
has-animation-only-dirty-descendants flag or has animation restyle hints.
Also we will use this flag to detect whether we need to trigger CSS transitions
or not.
We need a scope to restore rule_node_changed that were borrowed by the closure.
This closure function will be used for animation-only restyles as well.
Correct viewport test references
These references were using an incorrect value for the expected
container width. Now that WebRender is no longer clipping to stacking
context boundaries the rendered width is correct (100% of viewport
width = 240px).
