per wikitech, not sure we want this now.

any css adjustments can wait until next deployment, and if really
needed, can be done in site css as temporary measure.

Revert "Set font of the wb-firstHeading toolbar back to sans-serif"

This reverts commit de8b623b5e2877011cfcb511a73f98a4d67c212b.

Change-Id: I211ce064dd1947c49bd1bf83880c823f397433d2
Merge "per wikitech, not sure we want this now." into mw1.23-wmf21