This assumes that there are no ligatures that span across multiple
words. Since we have a per-word shape cache, this is a safe assumption
as of now. I have left comments to ensure that, if and when this is
revisted, we make sure to handle it properly.
The ligature disabling code has been manually verified, but I was unable
to reftest it. (The only way I could think of would be to create an
Ahem-like font with a ligature table, but that would be an awful lot of
work.)
Near as I can tell, the method used to apply the spacing (manually
inserting extra advance post-shaping) matches Gecko.
The Unicode awareness of `text-transform` is implemented as well as
possible given the Rust standard library's Unicode support. In
particular, the notion of an alphabetic character is used instead of a
letter.
Gecko has a subclass of text run to handle text transforms, but I
implemented this in a simpler way.
construction to avoid cloning and moving flows so much.
Besides amounting to a 5%-10% win on a page with a lot of text, this
simplifies and refactors the text layout code.
This implements fragment merging, in order to incrementally reflow linebroken
text. This makes the `whitespace_pre.html` reftest pass with incremental reflow
turned on with `-i`.
* Enabled acid2 on mac + linux. Updated the reference image. The only difference from the
real acid2 now is the paint order and a 1 pixel horizontal offset on the nose.
* Change line-height to be calculated correctly.
* Apply enclosing element style to text fragments.
