Change quick setting min_num_tiles number and text to resources value.

Bug: 130030850
Test: manually test by removing quick setting tile until we have 6. The
system will stop them at 6 and showing message "You need at least 6
tiles".

Change-Id: If2a4a42a4d3859908a2b529e2faae214fe6cebb6
(cherry picked from commit ad0a6fdb)