Now that cbindgen and rust support const generics, it seems more simple.
This centralizes all the relevant font constants etc in rust and avoids
conversions when going from rust to C++ and vice versa.
Differential Revision: https://phabricator.services.mozilla.com/D148847
Add LinearFunction to TimingFunction. Because the linear function is a
variable list of linear stops, the enum is no longer Copyable.
Differential Revision: https://phabricator.services.mozilla.com/D146837
Make the representation the same between Gecko and Servo code. This will
enable further clean-ups in the future.
Make serialization be correct, serializing as identifier unless it's an
invalid one (in which case we serialize as a string).
This changes our stringification behavior in the specified style, but
now it will match the computed style and be more correct over-all.
Differential Revision: https://phabricator.services.mozilla.com/D144473
This mostly just moves code around, to minimize potential behavior
changes. There are some cleanups that we should try to do long term
(this "have an array with n different counts" is pretty weird).
But for now this should unblock people.
The destination struct (nsStyleUIReset) was chosen mainly because it's
small and non-inherited, and it doesn't seem like a worse place than
nsStyleDisplay.
Differential Revision: https://phabricator.services.mozilla.com/D144183
* style: Simplify selector flag setting now that flag setting is atomic
These bits are write-only, actually, and we don't even need to read
them.
Differential Revision: https://phabricator.services.mozilla.com/D141888
* Further changes required by Servo
* style: Support media queries for dynamic-range and video-dynamic-range
This is a stub that only matches "standard" for all platforms.
Differential Revision: https://phabricator.services.mozilla.com/D141053
* style: Remove :-moz-lwtheme-{brighttext,darktext}
They are just convenience for :root[lwthemetextcolor="light"] (and dark,
respectively), but they generally shouldn't be used for dark mode
theming. In the past it was the only way to do it but now we have
prefers-color-scheme.
While at it, change lwthemetextcolor to be "lwtheme-brighttext" for
consistency with similar code we have for popups etc, and move it to
_setDarkModeAttributes.
While at it, remove layout.css.moz-lwtheme.content.enabled (which is
false always, we unshipped these from content successfully).
Differential Revision: https://phabricator.services.mozilla.com/D141593
* style: layout.css.moz-locale-dir.content.enabled
We successfully removed these from content in bug 1740230 (Firefox 96).
Differential Revision: https://phabricator.services.mozilla.com/D141727
* style: Really honor background-color: transparent in HCM even for form controls
I forgot we were doing this "revert-or-initial" shenanigans (which is needed
for stuff like link colors to be honored), so we need to early-return.
Use a more explicit test rather than a reftest for this.
Differential Revision: https://phabricator.services.mozilla.com/D142063
* style: Ignore unchanged property for scroll-linked effect detector
I think this is cleaner.
Differential Revision: https://phabricator.services.mozilla.com/D141737
* style: Allow to derive Parse/ToCss/SpecifiedValueInfo on bitflags
We keep getting this pattern of properties that have a set of joint and
disjoint flags, and copy-pasting or writing the same parsing and
serialization code in slightly different ways.
container-type is one such type, and I think we should have a single way
of dealing with this, thus implement deriving for various traits for
bitflags, with an attribute that says which flags are single vs mixed.
See docs and properties I ported. The remaining ones I left TODOs with,
they are a bit trickier but can be ported with some care.
Differential Revision: https://phabricator.services.mozilla.com/D142418
* Further changes required by Servo
* style: Implement parsing / serialization for container{,-type,-name} CSS properties
Two noteworthy details that may seem random otherwise:
* Moving values around in nsStyleDisplay is needed so that the struct
remains under the size limit that we have to avoid jumping allocator
buckets.
* All the test expectation churn is because tests depend on
`container-type: size` parsing to run, and now they run. Tests for
the relevant bits I implemented are passing, with the only exception
of some `container-name-computed.html` failures which are
https://github.com/w3c/csswg-drafts/issues/7181. Safari agrees with
us there.
Other notes when looking at the spec and seeing how it matches the
implementation:
* `container` syntax doesn't match spec, but matches tests and sanity:
https://github.com/w3c/csswg-drafts/issues/7180
* `container-type` syntax doesn't _quite_ match spec, but matches tests
and I think it's a spec bug since the definition for the missing
keyword is gone:
https://github.com/w3c/csswg-drafts/issues/7179
Differential Revision: https://phabricator.services.mozilla.com/D142419
* style: Remove assert that doesn't hold for text-decorations because of presentation hints
MANUAL PUSH: Orange fix CLOSED TREE
* style: Migrate `<th>` `text-align` behaviour from presentation hint to UA CSS
Differential Revision: https://phabricator.services.mozilla.com/D142494
* style: Deduplicate TokenList values faster
Remember whether we have already de-duplicated them once and avoid doing
that again.
This is an alternative approach that doesn't add overhead to attribute
setting in the general case.
Differential Revision: https://phabricator.services.mozilla.com/D142813
* style: Inherit used color-scheme from embedder <browser> elements
This allows popups and sidebars to use the chrome preferred
color-scheme.
This moves the responsibility of setting the content-preferred color
scheme to the appropriate browsers to the front-end (via tabs.css).
We still return the PreferredColorSchemeForContent() when there's no
pres context (e.g., for display:none in-process iframes). We could
potentially move a bunch of the pres-context data to the document
instead, but that should be acceptable IMO as for general web content
there's no behavior change in any case.
Differential Revision: https://phabricator.services.mozilla.com/D142578
* Further changes required by Servo
* style: Add basic @container rule parsing and boilerplate
For now parse a MediaFeatureCondition. That needs being made more
specific, but that is probably worth its own patch.
Differential Revision: https://phabricator.services.mozilla.com/D143192
* Further changes required by Servo
* style: Tweak cascade priority to split writing-mode and font properties
This makes the worst case for cascade performance slightly more
expensive (4 rather than three declaration walks), but my hope is that
it will make the average case faster, since the best case is now just
two walks instead of three, and writing mode properties are somewhat
rare.
This needs a test, but needs to wait until the writing-mode dependent
viewport units land (will wait to land with a test).
Differential Revision: https://phabricator.services.mozilla.com/D143261
* style: Implement new {small,large,dynamic} viewport units
Differential Revision: https://phabricator.services.mozilla.com/D143252
* Further changes required by Servo
* style: Implement new *vi and *vb units
Differential Revision: https://phabricator.services.mozilla.com/D143253
* style: Implement prefers-contrast: custom and let prefers-contrast ride the trains
Differential Revision: https://phabricator.services.mozilla.com/D143198
* style: Join servo style threads during shutdown
I was unable to change the BLOOM_KEY field to no longer be leaked, as the TLS
is also accessed on the main thread, which is not exited before the leak
checker shuts down.
Differential Revision: https://phabricator.services.mozilla.com/D143529
* Further changes required by Servo
* style: Fix visited handling after bug 1763750
Before bug 1763750, we unconditionally called compute_writing_mode,
which got the writing mode from the cascade mode for visited styles.
However after that bug we only do that if we apply any
writing-mode-related property.
We could just call compute_writing_mode unconditionally, but instead it
seems better to skip all that work for visited cascade and reuse the
mechanism introduced in that bug to only apply the visited-dependent
longhands.
We assert that all visited-dependent longhands are "late" longhands, so
as to also avoid applying the font group and such.
Differential Revision: https://phabricator.services.mozilla.com/D143490
* style: Clean-up viewport unit resolution a bit
I should've caught this when reviewing the new viewport units but alas :-)
Differential Revision: https://phabricator.services.mozilla.com/D143856
* style: Implement `contain: inline-size`
Differential Revision: https://phabricator.services.mozilla.com/D143501
* style: Simplify media query evaluation code a bit
This patch:
* Removes generic <ident> support for media features. These were used
for some privileged media features but are no longer used.
* Simplifies media feature getters by shifting the responsibility of
dealing with RangeOrOperator to the caller. This makes it easier to
implement container-query / mediaqueries-4 syntax, and also cleans up
the code a bunch.
There should be no change in behavior.
Differential Revision: https://phabricator.services.mozilla.com/D144051
* Further changes required by Servo
* style: Move transitions and animations to nsStyleUIReset
This mostly just moves code around, to minimize potential behavior
changes. There are some cleanups that we should try to do long term
(this "have an array with n different counts" is pretty weird).
But for now this should unblock people.
The destination struct (nsStyleUIReset) was chosen mainly because it's
small and non-inherited, and it doesn't seem like a worse place than
nsStyleDisplay.
Differential Revision: https://phabricator.services.mozilla.com/D144183
* Further changes required by Servo
* style: Make media feature evaluation take a computed::Context
This has no behavior change right now, but will simplify sharing code
with container queries.
Container queries will have container information in the
computed::Context (this is necessary anyways for container-based units),
so this avoids having to have different code for media and container
queries.
Differential Revision: https://phabricator.services.mozilla.com/D144152
* Further changes required by Servo
* style: Add scroll() to animation-timeline for style system
scroll() is defined in the spec proposal, and there is a temporary spec:
https://drafts.csswg.org/scroll-animations-1/rewrite#scroll-notation.
The spec is still under development, so we don't drop the orignal
scroll-timeline at rule. Instead, we add a new scroll() notation to
animation-timeline, and support both syntax for now.
Differential Revision: https://phabricator.services.mozilla.com/D143417
* style: Tweak contain bitflag definition order to avoid static constructors
This has no behavior change otherwise. The STRICT definition depended on
SIZE, which was defined later. That's fine in Rust, but in C++ it causes
the initialization to be dynamic because it doesn't have the definition
of SIZE yet (ugh).
This is the fix for the regression, though the following patch turns on
constexpr support in cbindgen, which would've caught this at build-time,
and guarantees that we don't have extra static constructors.
Differential Revision: https://phabricator.services.mozilla.com/D144316
* style: Move some of the media query code to a more generic queries module
No behavior change, just moving and renaming files.
The code in the "queries" module will be shared between @media and
@container.
@media has some other code that container queries doesn't need like
MediaList / MediaType / etc. That remains in the media_queries module.
Differential Revision: https://phabricator.services.mozilla.com/D144435
* Further changes required by Servo
* style: cleanup animation-name
Make the representation the same between Gecko and Servo code. This will
enable further clean-ups in the future.
Make serialization be correct, serializing as identifier unless it's an
invalid one (in which case we serialize as a string).
This changes our stringification behavior in the specified style, but
now it will match the computed style and be more correct over-all.
Differential Revision: https://phabricator.services.mozilla.com/D144473
* Further changes required by Servo
* style: Add support for parsing container-query-specific features
There are some mediaqueries-5 features that we still don't support and
explain the remaining failures in at-container-{parsing,serialization}.
Differential Revision: https://phabricator.services.mozilla.com/D144446
* Further changes required by Servo
* style: Introduce Optional<T> to represent optional values in the style system
cross-fade() was kinda doing this in its own way with PercentOrNone, but
since now we have more use-cases for this we should probably make this a
slightly more general solution.
I added some convenience APIs, but they're unused as of this patch so
let me know if you want them gone.
Differential Revision: https://phabricator.services.mozilla.com/D144831
* style: Fix insertRule with layer statements before imports
We need to do a bit more nuanced check because @layer statements might
go before imports.
Differential Revision: https://phabricator.services.mozilla.com/D144996
* style: Factor out parsing the query feature name
No behavior change.
Differential Revision: https://phabricator.services.mozilla.com/D145229
* style: Refactor media feature expression representation in preparation to support multi-range syntax
No behavior change.
Depends on D145229
Differential Revision: https://phabricator.services.mozilla.com/D145230
* style: Implement media feature expression multi-range syntax
Differential Revision: https://phabricator.services.mozilla.com/D145231
* style: Remove proton places tooltip code
There's nobody working on it, and tooltips should hopefully be nice
enough after recent changes (bug 1765423).
Having it enabled causes artifacts like bug 1767815 comment 3. We can
always rescue this from hg history if needed.
Differential Revision: https://phabricator.services.mozilla.com/D145621
* style: Simplify selector flags setup even more
In my investigation for bug 1766439, I am digging into why selector
matching regressed.
It doesn't help that the selector-matching code is instantiated a
gazillion times (so there's a ton of copies of the relevant functions).
This was needed in the past because we had different ways of setting the
selector flags on elements, but I unified that recently and now we only
need to either set them or not. That is the kind of thing that
MatchingContext is really good for, so pass that instead on
MatchingContext creation.
Differential Revision: https://phabricator.services.mozilla.com/D145428
* Further changes required by Servo
* style: Track @container condition id in style rules
Much like we track layer rules. Consolidate that "containing rule state
we pass down while building the cascade data" in a single struct that we
can easily restore.
For now, do nothing with it. I want to land this patch separately
because it touches the Rule struct and CascadeData rebuilds, which both
are performance sensitive.
Its layout shouldn't change because I also changed LayerId to be a u16
(this shouldn't matter in practice, since LayerOrder is already a u16).
Differential Revision: https://phabricator.services.mozilla.com/D145243
* Further changes required by Servo
* style: Fix layer statement rules with multiple layer names
MANUAL PUSH: Trivial orange fix CLOSED TREE.
* style: Implement piecewise linear function
Differential Revision: https://phabricator.services.mozilla.com/D145256
* style: Convert specified value tests to compile-time tests
These were written at a time where std::mem::size_of wasn't a `const fn` in
Rust.
Now that it is, we can make these tests live in the style crate, and the build
not to compile if they fail.
Differential Revision: https://phabricator.services.mozilla.com/D146103
* Further changes required by Servo
* style: Move size of tests to compile-time tests in the style crate
Same reasoning as the previous commit.
Differential Revision: https://phabricator.services.mozilla.com/D146104
* Further changes required by Servo
* style: Lint and 32-bit build fix.
MANUAL PUSH: Bustage fix CLOSED TREE
* style: Implement 'update' media feature
Differential Revision: https://phabricator.services.mozilla.com/D146338
* style: Clean up unused -moz-window-shadow values
After bug 1768278 and bug 1767815 there's no more uses of the cliprounded value
in the tree (also it causes artifacts on HiDPI screens so we probably don't
want new usages).
The "sheet" value is unused, and the other values other than "default" and
"none" are only derived from "default", so they don't need to be exposed in the
style system.
Differential Revision: https://phabricator.services.mozilla.com/D145821
* style: More container queries plumbing
Provide container information in computed::Context and use it to resolve
the container queries.
This still fails a lot of tests because we are not ensuring that layout
is up-to-date when we style the container descendants, but that's
expected.
Differential Revision: https://phabricator.services.mozilla.com/D146478
* Further changes required by Servo
* style: Ensure options in listbox selects are not stacking contexts by default
We could have a different property or something but this seems
reasonable as well probably.
Differential Revision: https://phabricator.services.mozilla.com/D146994
* style: Implement overflow-clip-margin: <length>
Differential Revision: https://phabricator.services.mozilla.com/D146432
* style: Change order of container shorthand
Since the initial value of container-type is an open issue [1],
I'm leaving that as-is for now.
[1] https://github.com/w3c/csswg-drafts/issues/7202
Differential Revision: https://phabricator.services.mozilla.com/D147338
* style: Make modal dialog code more generic, and make it apply to fullscreen too behind a pref
For now, don't turn it on by default yet, because I want to wait for
more discussion in https://github.com/w3c/csswg-drafts/issues/6965 and
so on. But I think the code is simple enough to land this.
Differential Revision: https://phabricator.services.mozilla.com/D147295
* style: Cache computed styles objects display: none subtrees
This reuses our existing undisplayed style generation, but in a
per-document rather than per-nsComputedDOMStyle object, which means that
we can avoid re-resolving styles of elements in display: none subtrees
much more often.
This brings the test-case in the bug to par with other browsers or
better, and is much simpler than the initial approach I tried back in
the day.
Differential Revision: https://phabricator.services.mozilla.com/D147547
* Further changes required by Servo
* style: Parse scroll-snap-stop style and propagate it to APZ side
Depends on D146147
Differential Revision: https://phabricator.services.mozilla.com/D145850
* style: Update color-mix() syntax to match the current spec
Test expectation updates for this in the latest patch of the bug.
Differential Revision: https://phabricator.services.mozilla.com/D147002
* Further changes required by Servo
* style: Make the color interpolation code more generic
It's really piece-wise premultiplied interpolation, with a special-case
for hue, so centralize the implementation.
Differential Revision: https://phabricator.services.mozilla.com/D147003
* style: Implement more color-mix() color-spaces
We had code to convert between these and the latest draft supports them so...
Differential Revision: https://phabricator.services.mozilla.com/D147004
* style: Fix color-mix() percentage normalization
Differential Revision: https://phabricator.services.mozilla.com/D147005
* style: Fix hue adjustment to match the spec
The value to sum is tau, not pi. This was caught by some tests, see
https://drafts.csswg.org/css-color/#shorter
Differential Revision: https://phabricator.services.mozilla.com/D147006
* style: Do hue interpolations in degrees rather than radians. r=barret
This gives us a bit more precision.
Differential Revision: https://phabricator.services.mozilla.com/D147007
* style: Improve Percentage -> LengthPercentage conversion
This doesn't change behavior because we only use them for images that
have no clamping.
Depends on D147008
Differential Revision: https://phabricator.services.mozilla.com/D147511
* style: Remove some dead vibrancy code
Drive-by cleanup.
Differential Revision: https://phabricator.services.mozilla.com/D147698
* style: Fix warnings about whitelist/blocklist functions being deprecated in bindgen 0.59
Differential Revision: https://phabricator.services.mozilla.com/D147695
* style: Update style to arrayvec 0.7
Differential Revision: https://phabricator.services.mozilla.com/D147476
* style: Update style to uluru 3.0
Differential Revision: https://phabricator.services.mozilla.com/D147477
* style: Remove -moz-scrollbar-thumb-proportional
It unconditionally matches on all platforms, so it's not returning any useful information.
Depends on D147689
Differential Revision: https://phabricator.services.mozilla.com/D147690
* style: Use ColorMix for interpolated colors in the computed style rather than ComplexColorRatios
This among other things preserves the right color-space when
interpolating currentColor.
Differential Revision: https://phabricator.services.mozilla.com/D147512
* Further changes required by Servo
* style: Add an input-region-margin to widgets, and implement it on Linux
Recompute the input region when resizing the widget and so on, and use
it to check for rollups.
Depends on D148211
Differential Revision: https://phabricator.services.mozilla.com/D148222
* Avoid complaints from ./mach test-tidy
* Update test expectations
---------
Co-authored-by: Emilio Cobos Álvarez <emilio@crisal.io>
Co-authored-by: Brad Werth <bwerth@mozilla.com>
Co-authored-by: David Shin <dshin@mozilla.com>
Co-authored-by: Hiroyuki Ikezoe <hikezoe.birchill@mozilla.com>
Co-authored-by: Nika Layzell <nika@thelayzells.com>
Co-authored-by: Boris Chiou <boris.chiou@gmail.com>
Co-authored-by: Autumn on Tape <autumn@cyfox.net>
Co-authored-by: Mike Hommey <mh+mozilla@glandium.org>
This patch adds the animation-timeline longhand property. For
shorthand, we will do that in the next patch.
This patch includes the aut-generated code in
devtools/shared/css/generated/properties-db.js, by `./mach devtools-css-db`.
Note:
1. we will use this property in Bug 1676791. For now, only make sure
we parse it and serialize it correctly.
2. The syntax of animation-timeline may be updated, based on the spec
issue: https://github.com/w3c/csswg-drafts/issues/6674.
However, it's not a big problem to update it later, so we still can
prototype this property based on the current version of spec.
Differential Revision: https://phabricator.services.mozilla.com/D126450
This changes font-family storage to reuse the rust types, removing a
bunch of code while at it. This allows us to, for example, use a single
static font family for -moz-bullet and clone it, rather than creating a
lot of expensive copies.
Differential Revision: https://phabricator.services.mozilla.com/D118011
This parsing is hidden behind the pref layout.css.page-size.enabled.
It isn't ideal that we parse this as a property, but we can't treat it as a
descriptor because of compatibility issues with other browsers. There are also
outstanding spec issues related to how descriptors like page-size are cascaded,
and whether the !important specifier is valid or not.
Differential Revision: https://phabricator.services.mozilla.com/D103958
This avoids arbitrary precision loss when computing REM units and so on,
which is particularly important if we ever change the base of our app
units (but useful regardless).
Differential Revision: https://phabricator.services.mozilla.com/D79928
This also fixes some backwards logic in nsBlockFrame::ReflowDirtyLines, and adds
some static assertions to nsGenericHTMLElement that almost cause a very subtle
bug.
Depends on D63792
Differential Revision: https://phabricator.services.mozilla.com/D63793
The trickier part is that we represent -moz-image-rect as a Rect() type instead
of image with non-null clip-rect. So we need to add a bit of code to
distinguish "image request types" from other types of images.
But it's not too annoying, and we need to do the same for fancier images like
image-set and such whenever we implement it, so seems nice to get rid of
most explicit usages of nsStyleImage::GetType().
Differential Revision: https://phabricator.services.mozilla.com/D62164
Tweak the ShapeSourceRepresentation so that it doesn't store Option<>s.
Some renames so that GeometryBox doesn't conflict with the Gecko type, and some
other usual bits / re-exports to deal with cbindgen and generics.
Also, drive-by derive parsing of GeometryBox as it's trivial.
Doing this unfortunately is not possible without removing nsStyleImage first, so
let's do that before.
This makes us serialize in the shortest form for shape-outside, but that's what
we should do anyway.
(aside: the shapes code is a bit too generic, maybe we should unify
ClippingShape and FloatAreaShape...)
Differential Revision: https://phabricator.services.mozilla.com/D62163
ImageLayer is almost the only usage of Image, so keeping them in the same enum
makes the resulting C++ struct smaller, and makes it map more cleanly to
nsStyleImage.
Differential Revision: https://phabricator.services.mozilla.com/D62161
This removes nsStyleImageRequest by moving the load state to LoadData instead
(where other lazy state like the resolved URL and load id lives).
That way we can use cbindgen for more stuff (there's no blocker for using it for
all images now), and we can undo the image tracking shenanigans that I had to do
in bug 1605803 in nsImageFrame.
This removes the mDocGroup member because well, there's no real upside of that
now that quantum DOM is not a thing.
It also removes the static clones of the image requests, and the need for each
computed value instance to have its own request. These were needed because we
needed the image loader for the particular document to observe the image
changes. But we were also tracking the request -> loader for other purposes.
Instead, Now all the images get loaded with GlobalImageObserver as a listener,
which looks in the image map and forwards the notification to all the interested
loaders instead dynamically.
The style value is only responsible to load the image, and no longer tracks /
locks it. Instead, the loader does so, via the image tracker.
Differential Revision: https://phabricator.services.mozilla.com/D58519
This cleans up and also allows us to keep the distinction between content: none
and content: normal, which allows us to fix the computed style we return from
getComputedStyle().
Do this last bit from the resolved value instead of StyleAdjuster, because
otherwise we need to tweak every initial struct for ::before / ::after.
Differential Revision: https://phabricator.services.mozilla.com/D58276
Font code is the only thing that was using Au in the style system without
interfacing with Gecko, and there was no real reason for it to do so.
This slightly simplifies the code.
Differential Revision: https://phabricator.services.mozilla.com/D57248
This is consistent with the `order` property anyhow, and allows to simplify some
code.
Negatives are still not parsed, but rust uses a similar representation for all
CSS <integer> values and so should C++.
Differential Revision: https://phabricator.services.mozilla.com/D42912
These two bugs (bug 1572738 and bug 1572451) are stylo regressions.
When font-family changes, we try to recompute the font-size with a length /
percentage combinations in case the generic family changes, so the user
preferences are kept.
When calc() is involved, we clamp to non-negative too early, via
NonNegativeLength::scale_by.
I think we should generally dump this "try to track font-size across calc()"
thingie, as as various comments note it is not quite perfect, and it's not clear
how it should work in presence of min()/max().
This patch fixes the issue and simplifies code a bit, I may consider removing
this altogether in a follow-up.
Differential Revision: https://phabricator.services.mozilla.com/D41776
I'm _really_ sorry for the size of the patch. I tried to do this in two steps
but it was a lot of work and pretty ugly.
This patch makes us use cbindgen for grid-template-{rows,columns}, in order to:
* Make us preserve repeat() at computed-value time. This is per spec since
interpolation needs to know about repeat(). Except for subgrid, which did the
repeat expansion at parse-time and was a bit more annoying (plus it doesn't
really animate yet so we don't need it to comply with the spec).
* Tweaks the WPT tests for interpolation to adopt the resolution at:
https://github.com/w3c/csswg-drafts/issues/3503.
Trade-off here, as this patch stands, is that this change makes us use less
long-living memory, since we expand repeat() during layout, but at the cost of a
bit of CPU time during layout (conditional on the property applying though,
which wasn't the case before). It should be very easy to store a cached version
of the template, should this be too hot (I expect it isn't), or to change the
representation in other ways to optimize grid layout code if it's worth it.
Another trade-off: I've used SmallPointerArray to handle line-name merging,
pointing to the individual arrays in the style data, rather than actually
heap-allocating the merged lists. This would also be pretty easy to change
should we measure and see that it's not worth it.
This patch also opens the gate to potentially improving memory usage in some
other ways, by reference-counting line-name lists for example, though I don't
have data that suggests it is worth it.
In general, this patch makes much easier to tweak the internal representation of
the grid style data structures. Overall, I think it's a win, the amount of magic
going on in that mako code was a bit huge; it took a bit to wrap my head around
it.
This patch comments out the style struct size assertions. They will be
uncommented in a follow-up patch which contains some improvements for this type,
which are worth getting reviewed separately.
Also, this patch doesn't remove as much code as I would've hoped for because of
I tried not to change most of the dom/grid code for inspector, but I think a
fair bit of the nsGridContainerFrame.cpp code that collects information for it
can be simplified / de-copy-pasted to some extent. But that was a pre-existing
problem and this patch is already quite massive.
Differential Revision: https://phabricator.services.mozilla.com/D36598
