Fix inline layout of table cells impacted by rowspan
This is part of the fix for #11297. This PR fixes the inline layout of table cells impacted by row-spanning cells from previous rows. A separate PR to follow will fix the table block size calculations to account for rowspan.
This PR doesn't yet include any test changes. If it doesn't cause any existing tests to pass, I will add a new test to it.
r? @pcwalton
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The primary idea of this patch is to ditch the rigid enum of Previous/Current
styles, and replace it with a series of indicators for the various types of
work that needs to be performed (expanding snapshots, rematching, recascading,
and damage processing). This loses us a little bit of sanity checking (since
the up-to-date-ness of our style is no longer baked into the type system), but
gives us a lot more flexibility that we'll need going forward (especially when
we separate matching from cascading). We also eliminate get_styling_mode in
favor of a method on the traversal.
This patch does a few other things as ridealongs:
* Temporarily eliminates the handling for transfering ownership of styles to the
frame. We'll need this again at some point, but for now it's causing too much
complexity for a half-implemented feature.
* Ditches TRestyleDamage, which is no longer necessary post-crate-merge, and is
a constant source of compilation failures from either needing to be imported
or being unnecessarily imported (which varies between gecko and servo).
* Expands Snapshots for the traversal root, which was missing before.
* Fixes up the skip_root stuff to avoid visiting the skipped root.
* Unifies parallel traversal and avoids spawning for a single work item.
* Adds an explicit pre_traverse step do any pre-processing and determine whether
we need to traverse at all.
MozReview-Commit-ID: IKhLAkAigXE
Urlmageddon
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Still needs a bunch of code in net to be converted in order to get more
advantage of this for images and stuff, but meanwhile this should help quite a
bit with #13778.
Still wanted to get this in.
r? @SimonSapin
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The style system never actually does anything with the document. This allows us
to remove a bunch of stubbing on the Gecko side and streamline some things on
the Servo side in future patches.
We also make sure that an element never has an ElementData with ElementDataStyles::Uninitialized,
and eagerly call prepare_for_styling whenever an ElementData is instantiated.
MozReview-Commit-ID: 9YP6eSmdMt0
Instead of maintaining a dummy restyle damage field for text nodes, we can just
perform the necessary parent inheritance and is_changed adjustments on the fly
in ThreadSafeLayoutNode, simplifying the requirements on the style system.
MozReview-Commit-ID: DCqiCRLsLUF
A couple of changes here:
* Remove the option to unset with the dirty bit setters.
* Add an explicit API for setting text node style.
* Hoist has_changed handling into the restyle damage setter and text node style setter.
* Make set_style take a non-Option.
We don't need this for Gecko, and it's hard to implement in that case because
there's nowhere obvious to put it (we don't plan to create TSDs for non-dirty
nodes, and non-dirty nodes can have dirty children which require the
children_to_process atomic). There are various solutions here, but punting is
the easiest.
We'll need to rethink this if/when we need to do a bottom-up traversal for
Gecko.
