Fix nit comments on quick contact suggestion card.

1) Add suggestions limit number to integers.xml
2) Increase character limit or it 'll cause truncation.
3) Fix a bug when merge is canceled. Should not clear selected
   contact Ids.

BUG 21071527

Change-Id: Iaee6d4a60c1b7ffd2612235a9e68b7b2bebeaca3