Revert "Return the correct system font on OS X Mavericks."

This fix is broken and a working solution will replace it shortly.

This reverts commit 7c4c43afb36449c9fb2d281327423df8eb916d64

Change-Id: I764e7da6e7a52916b87650483271d9aed099ed2b
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>