This is partial revert of Iced1349e3ca750821d8882c551551f65bb569794.
Due to sorting of target family vectors, the font family order from XML
settings file is broken. Making unique operation stable doesn't fix the
issue completely since some font families are appended for the fallback
which also breaks the original order.
By this change, itemization becomes 3x slower than before if variation
selector is appended.
Bug: 29585939
Change-Id: I7c1a8a57f04111a30cd41a5cd5bec25fcfb3972e
4a4e6574c0