...for `text-justify: inter-character`.
We previously had this mapped in Enums.json, but the behaviour is
different: `a=b` in Enums.json keeps `a` around but makes it behave the
same as `b`. A legacy name alias is instead expected to replace `a`
with `b`, so we have to do that separately.
This exposed a few bugs which caused the following tests to behave
incorrectly:
- `tab-size-text-wrap.html`: This previously relied on a bug where we
incorrectly treated `white-space: pre` as allowing text wrapping. The
fix here is to implement the text-wrap CSS shorthand property.
- `execCommand-preserveWhitespace.html`: We don't correctly serialize
shorthand properties. This is covered by an existing FIXME in
`CSSStyleProperties::serialized()`
- `white-space-shorthand.html`: The last 5 subtests here fail as we
don't correctly handle shorthand properties in
`CSSStyleProperties::remove_property()`. This is covered by an
existing FIXME in said function.
At computed-value time, this is converted to whatever the parent's
computed value is. So it behaves a little like `inherit`, except that
an inherited start/end value uses the parent's start/end, which might
be different from the child's.
