Don't manually close the database.

Don't close and reopen the database in CDH.getWritableDatabase().
The reason we did this was to sqlite reload the sqlite_stat1 table,
but according to the document running "ANALYZE sqlite_master"
should be suffice.  (See http://www.sqlite.org/lang_analyze.html)

Also don't close the database helpers after upgrade in
ContactsUpgradeReceiver.  We don't have to do this.

Also, replaced the test-only constructors of the helpers with methods
with more explicit name, in order to make sure only the singleton
instances are used in the main code.

Bug 6104842

Change-Id: I76a7d1b8f7b6462b97f627d722feaa03967cb18f
7 files changed