Resolve stroke-width 'em' units against unzoomed font size

When resolving style for the 'stroke-width' property we would use
CSSToLengthConversionData::CopyWithAdjustedZoom() with an argument of 1
to get an "unzoomed" length. The FontSizes object was however not
adjusted, so still carried zoomed base font sizes.

Make a new method on StyleResolverState that returns an
CSSToLengthConversionData that uses unzoomed unit bases, basing it on
the existing FontSizeConversionData() method which does roughly the
same thing except it uses the parent style for unit bases.

Bug: 933689
Change-Id: Icfbc59a641f0dc2d94f00ba5f3e9a15b36f8c195
Reviewed-by: Anders Hartvoll Ruud <>
Commit-Queue: Fredrik Söderquist <>
Cr-Commit-Position: refs/heads/master@{#634750}
4 files changed