[cros] Bubble font family fix.

BUG=chromium-os:113315
TEST=Manual: see bug description.

Review URL: https://chromiumcodereview.appspot.com/9375008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@121223 0039d316-1c4b-4281-b951-d872f2087c98