Settings : Launch only contacts picker for blacklist entry

Change-Id: I266d1ad7f1aab745728b33490268cb197188f2b3
Settings: Fix isPackageInstalled logic.

    - If package is null, isPackageInstalled returned true.
    - Return false if null, always.
    - PS2: Fix codestyle
Change-Id: If2bf41e4c9520195d56e327a447d7085daab3154