Instead of using the first font from the FontCascadeList for all glyphs
in a text, we perform a text shaping process that finds a suitable font
for each glyph and returns a list of glyph runs, where each glyph run
represents consecutive glyphs using the same font.
Canvas text painting needs to support per-glyph font fallbacks, which
means we can't hand over responsibility for text shaping to Skia and
instead need to extract glyph paths from our own shaped GlyphRun.
Instead of indiscriminately clearing the cache for all anonymous boxes,
we now only clear it for those that were generated by a non-anonymous
box in need of layout update.
This increases the cache hit rate and allows us to avoid more work.
These elements are quite special, so let's treat them like we do for
substantial CSS display changes and rebuild the layout tree starting
from the parent element instead of self.
Before this change, we were going through the chain of base classes for
each IDL interface object and having them set the prototype to their
prototype.
Instead of doing that, reorder things so that we set the right prototype
immediately in Foo::initialize(), and then don't bother in all the base
class overrides.
This knocks off a ~1% profile item on Speedometer 3.
Many elements never end up needing this string, so instead of eagerly
generating it in the Element constructor, let's defer it until someone
actually requests it.
Knocks off a ~1% profile item on Speedometer3's jQuery test.
Instead, let JS::NativeFunction store the AK::Function directly, and
take care of conservatively marking its captured data.
This avoids an extra GC allocation for every JS::NativeFunction.
This will cause an exception to be thrown if user attempts to read from
the response stream of a failed request.
This is unfortunately not testable in CI. It requires a network response
(i.e. not a file:// URL). We also cannot import relevant WPT tests; they
exercise this condition with a python-generated response.
The basic idea is that style sheets can block script execution under
some circumstances. With this commit, we now handle the simplest cases
where a parser-inserted link element gets to download its style sheet
before script execution continues.
This improves performance on Speedometer 3 where JavaScript APIs that
depend on layout results (like Element.scrollIntoView()) would get
called too early (before the relevant CSS was downloaded), and so we'd
perform premature layout work. This work then had to be redone after
downloading the CSS anyway, wasting time.
Note that our Text/input/link-re-enable-crash.html test had to be
tweaked after these changes, since it relied on the old, incorrect,
behavior where scripts would run before downloading CSS.
Before this change, we were waiting for Document to lazily evaluate
sheet media and media rules. This often meant that we'd get two
full-document style invalidations: one from adding a new style sheet,
and one from the media queries changing state.
By evaluating the rules eagerly on insertion, we coalesce the two
invalidations into one. This reduces the number of full-document
invalidations on Speedometer 3 from 51 to 34.
We now cache the containing block (box) once at the start of layout,
which allows Layout::Node::containing_block() to return instantly
instead of doing tree traversal.
Removes a 0.7% profile item on Speedometer 3.
These are slightly unfortunate as we're crossing the library boundary,
but there's precedent with Object::is_dom_node(), and these are just
knocking down a few more items that were showing up in profiles.
The remaining AOs can stay where they are. This patch just sorts them in
spec order to match the other AO files. Section 8.1 is last, however, as
these are all templates and need the declarations of other AOs above.
The main streams AO file has gotten very large, and is a bit difficult
to navigate. In an effort to improve DX, this migrates TransformStream
AOs to their own file.
The main streams AO file has gotten very large, and is a bit difficult
to navigate. In an effort to improve DX, this migrates WritableStream
AOs to their own file.
