When deleting a db file,

Context.deleteDatabase() has to be called instead of File.delete()
to guarantee all db related files
like journal, wal, shm, etc are deleted together.

Signed-off-by:  <jangwon.lee&lt;jangwon.lee@lge.com>

Change-Id: I3c3d7dfa13ffbe709ab7d8a5c7cfe6cfa2864fea