text layout, and unify the inline layout paths for pre- and
normally-formatted text.
This fixes a lot of "jumpiness" and removes the `new_line_pos` stuff.
Closes#2260.
CSS-TEXT-3 § 7.3.
`text-justify: distribute` is not supported.
The behavior of `text-justify: none` does not seem to match what Firefox
and Chrome do, but it seems to match the spec.
Closes#213.
This used to conflict with the util crate from the standard library, which
has long since been removed.
The import in layout has not been changed because of a conflict with the
util mod there.
This property is used by approximately 55% of page loads.
To implement the line breaking behavior, the "breaking strategy" has
been cleaned up and abstracted. This should allow us to easily support
other similar properties in the future, such as `text-overflow` and
`word-break`.
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.
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.
