Avoid a panic when handling collapsing borders (fixes#7144)
There is no need to compute next_collapsed_borders_in_block_direction for all kind of flows when it's used only in the table row case. That also avoids a panic when the next child is a table colgroup (this should not happen when iterating over a table row).
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There is no need to compute next_collapsed_borders_in_block_direction for all
kind of flows when it's used only in the table row case. That also avoids a panic
when the next child is a table colgroup (this should not happen when iterating
over a table row).
layout: Improve our handling of inline absolute containing blocks.
Several issues are addressed in this commit:
* Inline flows now bubble up their absolute descendants instead of
making the inline flow the containing block for them. (In the future,
we will need to make the inline flow *sometimes* be the containing
block for them, but for now it improves sites to unconditionally
bubble up.)
* Fragments now look at their inline fragment context to determine
whether they are positioned.
* Inline flows now push the stacking-relative position of the absolute
containing block down to their inline-block fragments.
* Inline absolute hypothetical fragments can be containing blocks.
* Fixes the logic in
`containing_block_range_for_flow_surrounding_fragment_at_index`. The
condition to determine whether fragments are positioned was inverted!
* `Descendants`/`AbsDescendants` has been refactored in order to become
more friendly to inline absolute containing blocks in the future.
Improves the inline position of the green drop-down arrow in the Google
SERPs. (The block position is still wrong.)
r? @mbrubeck
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Several issues are addressed in this commit:
* Inline flows now bubble up their absolute descendants instead of
making the inline flow the containing block for them. (In the future,
we will need to make the inline flow *sometimes* be the containing
block for them, but for now it improves sites to unconditionally
bubble up.)
* Fragments now look at their inline fragment context to determine
whether they are positioned.
* Inline flows now push the stacking-relative position of the absolute
containing block down to their inline-block fragments.
* Inline absolute hypothetical fragments can be containing blocks.
* Fixes the logic in
`containing_block_range_for_flow_surrounding_fragment_at_index`. The
condition to determine whether fragments are positioned was inverted!
* `Descendants`/`AbsDescendants` has been refactored in order to become
more friendly to inline absolute containing blocks in the future.
Improves the inline position of the green drop-down arrow in the Google
SERPs. (The block position is still wrong.)
Fix panics in the script_task memory reporter.
These are caused by page_root being empty.
@jdm, I think it was #6874 that introduced these. I'm seeing them all the time when starting Servo on Reddit with memory profiling enabled. With this patch applied they go away.
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Implement a PerformanceActor.
This is necessary for the devtools "Start Recording Performance" button to
send a message.
(This message is not yet supported, so it leads to
'unexpected message type "startRecording" found for actor "performance4"'.)
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