1a41596bbf
Previously, we mapped left: anchor(left); to "Resolve anchor(left) with in horizontal axis" - However, this doesn't work for two reasons: 1. `left: anchor(left)` and `right: anchor(left)` have to return 2 different values to produce the identical result 2. We need side data for `left: anchor(inside)` and `right: anchor(outside)` Differential Revision: https://phabricator.services.mozilla.com/D247663