...with inline children. This fixes an issue when we ignore abspos boxes
contained by PaintableWithLines while calculating overflow rect size.
Lots of layout tests are affected, because now PaintableWithLines has
overflow rect.
`Text/input/DOM/Element-set-scroll-left.html` is also affected and now
matches other browsers.
Browsers such as Chrome and Firefox apply an arbitrary scale to the
current font size if `normal` is used for `line-height`. Firefox uses
1.2 while Chrome uses 1.15. Let's go with the latter for now, it's
relatively easy to change if we ever want to go back on that decision.
This also requires updating the expectations for a lot of layout tests.
The upside of this is that it's a bit easier to compare our layout
results to other browsers', especially Chrome.
This is a part of refactoring towards making the paintable tree
independent of the layout tree. Now, instead of transferring text
fragments from the layout tree to the paintable tree during the layout
commit phase, we allocate separate PaintableFragments that contain only
the information necessary for painting. Doing this also allows us to
get rid LineBoxes, as they are used only during layout.
This patch makes a few changes to the way we calculate line-height:
- `line-height: normal` is now resolved using metrics from the used
font (specifically, round(A + D + lineGap)).
- `line-height: calc(...)` is now resolved at style compute time.
- `line-height` values are now absolutized at style compute time.
As a consequence of the above, we no longer need to walk the DOM
ancestor chain looking for line-heights during style computation.
Instead, values are inherited, resolved and absolutized locally.
This is not only much faster, but also makes our line-height metrics
match those of other engines like Gecko and Blink.
Before, we were using the line height from NodeWithStyle::line_height()
to calculate the y offset for floats inside the IFC. However, this
value doesn't always correspond to the actual height of a line box. For
instance, adding a fragment for an inline-block might change the height
of the line box. With this change, we recalculate the height of the
line box after adding a new fragment and use this recalculated height
value to determine the y position for floats.
Fixes https://github.com/SerenityOS/serenity/issues/20982
