Fixes warnings from rust-lang/rust#44229 when `--enable-commonmark` is
passed to rustdoc.
This is mostly a global find-and-replace for bare URIs on lines by
themselves in doc comments.
First, we define computed::CSSPixelLength which contains a CSSFloat, a
pixel value, and then we replace computed::Length with CSSPixelLength.
Therefore, the |ComputedValue| of NoCalcLength, AbsoluteLength,
FontRelativeLength, ViewportPercentageLength, CharacterWidth, and
PhysicalLength is CSSPixelLength.
Besides, we drop NonNegativeAu, and replace computed::NonNegativeLength
with NonNegative<computed::Length>. (i.e. NonNegative<CSSPixelLength>)
BorderCornerRadius should always be non-negative, so we can implemennt
ToAnimatedValue for it directly, for properties:
1. border-{*}-radius
2. -moz-outline-{*}-radius
MozReview-Commit-ID: HEbeHz9Hfkd
Add values::computed::NonNegativeAu, so BorderSideWith could be computed
to this non-negative Au, for the following properties:
1. outline-width
2. border-{*}-width
3. column-rule-width
4. -webkit-text-stroke-width
MozReview-Commit-ID: ASHaB2F7VtM
NonNegativeNumber: for -moz-box-flex, flex-grow, and flex-shrink.
GreaterThanOrEqualToOneNumber: for stroke-miterlimit.
MozReview-Commit-ID: Kgbt99BPdVA
