Fix counters instantiating
As per https://drafts.csswg.org/css-lists/#instantiating-counters:
If innermost counter’s originating element is element or a previous
sibling of element, remove innermost counter from counters.
Fixed: 346974104
Change-Id: I938a13937cd629a9a4758483c0e118501629e302
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5630408
Reviewed-by: Vladimir Levin vmpstr@chromium.org
Commit-Queue: Daniil Sakhapov sakhapov@chromium.org
Cr-Commit-Position: refs/heads/main@{#1315384}