Previously we would serialize these as the empty string. eg, this: ``` <div style="grid-auto-columns: auto"></div> ``` would have a computed `grid-auto-columns` value of ``. (cherry picked from commit 7c2680b7efd2588cf2c5e595f7a60813dabf3b92)
Turns out we create a lot of these, mostly from places that don't return ErrorOr. The yak stack grows.
