Fixed the settings search for emergency alerts

1. The toggle "Vibrate" is renamed to "Vibration" so it's
   aligned with other vibration related settings.
2. Renamed the app label of CellBroadcastReceiver from
   "Cell Broadcasts" to "Emergency alerts" so it's
   consistent with the its entry name in Settings.
   Otherwise "Cell Broadcasts" is shown in the search result.
3. Add more meaningful keywords so people can find it easily.

Test: Manual. (See screenshot)
Bug: 111400757
Merged-In: I27655fb53df3b64d7484c75d3629a075567d9900
Change-Id: I27655fb53df3b64d7484c75d3629a075567d9900
(cherry picked from commit 6a196eb316eecedeb1f2b1045855ffa5e56df6da)
2 files changed