Revert "Add pseudo-classes to match on the state of the "dir" attribute." for preventing me from backing out a gecko-side patch
The gecko patches in bug 1373798 broke some gecko-side tests, but they also fixed a stylo build failure that started when this commit merged from servo to autoland, so this needs to get reverted so I can cleanly back out those gecko patches.
This reverts commit e4660c2b5b.
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