remove leak WaitResult List in startActivityMayWait

Change-Id: If169ef4474a6a38eb2957c806c6e7f8f7ce67783
Signed-off-by: Young-ho Cha <ganadist@gmail.com>
Disable usage of WAL in DatabaseHelper

According to SQLite documentation, WAL can not be used when database
partition is not accessible for writing (even when the client just
performs read operation).
However, such situation may happen when the partition is full.
As SettingsProvider should always be able to read a value of ANDROID_ID
from corresponding database, this commit disables usage of WAL.
Without this we risk ending up in a situation where /data is full
and the phone is unable to boot properly.

Change-Id: I1f79bbcd8d0f64bf35dc9d7b846bcfb2664d2eac