Collect all the preceding block-level siblings whose vertical margins
are collapsible. Both margin-top and margin-bottom now (previously,
we only considered the margin-bottom of siblings.)
Use the right margin in part-negative and all-negative situations.
We now distribute the line-height evenly between the space above and
below inline-level boxes. This noticeably improves our baseline
alignment in many cases.
Note that the "vertical-align: <length>" case is quite awkward, as the
extra height added by the offset baseline must count towards the line
box height.
There's a lot of room for improvement here, but this makes the buckets
container on Acid3 show up in the right place, with the right size.
Specifically HTMLIFrameElement and HTMLObjectElement. HTMLEmbedElement
will gain it automatically once it's also converted to inherit from
BrowsingContextContainer.
Make sure we use the create_anonymous_wrapper() helper function whenever
wrapping inline content in anonymous wrapper blocks. We were forgetting
to do this in one case, which led to some wrapper blocks having 0px
font-size and line-height.
Normally, paintable coordinates are relative to the nearest containing
block, but in the SVG case, since <svg> doesn't form a containing block,
we have to specialize the computation of SVGPaintable::absolute_rect().
When I wrote the An+B parser, it was guaranteed to have no
non-whitespace tokens after it. This is no longer true with the `of
foo` syntax, so this patch corrects the logic when there is no `+B`
segment.
This makes this case shown on Twitter work correctly. :^)
https://twitter.com/simevidas/status/1506657566012678151
We don't yet take the spread-distance parameter into account, since we
don't have a way to "inflate" the text shadow.
Also, I'm not sure if we need to inflate the shadow slightly anyway.
Blurred shadows of our pixel fonts seem very faint. Part of this is
that a blur of < 3px does nothing, see #13231, but even so we might
want to inflate it a little.
`text-shadow` does not support this, so this way we can still use the
same parsing code.
It's OK that we still assign a ShadowPlacement value to the
ShadowStyleValue, since it will just get ignored when painting
text-shadows, but if it appears in the property value then that is a
syntax error.
The `text-shadow` property is almost identical to `box-shadow`:
> Values are interpreted as for box-shadow [CSS-BACKGROUNDS-3].
> (But note that the inset keyword are not allowed.)
So, let's use the same data structures and parsing code for both. :^)
The HTMLObjectElement spec is set up to ignore application/octet-stream
MIME types only. For this to work, we need to implement the MIME type
sniffing algorithm so that all unknown MIME types become mapped to the
application/octet-stream type. Until then, ignore all application/ MIME
types as we won't be able to display them anyways.
We were using the literal string "unknown" as the unknown MIME type,
which caused us to treat the object as a nested browsing context (as
"unknown" does not start with "image/"). Use an Optional instead to
prevent this mishap.
