Log previous SQL statement also when logging "COMMIT;" operations.

Previously, as somewhat expected, the top SQL statements showing up in
the SQL analysis dashboards from developer phones was just "COMMIT;"
statements, which is pretty uselessly ambiguous.

Now the logs for commit operations look like:

I/db_operation( 1249): [/data/data/com.google.android.gsf/databases/subscribedfeeds.db,COMMIT;DELETE FROM _deleted_feeds WHERE _sync_account=? AND _syn,461,com.google.process.gapps,100]
I/db_operation( 1290): [/data/data/com.android.providers.contacts/databases/contacts2.db,COMMIT;SELECT account_name, account_type FROM _sync_state,126,android.process.acore,100]
I/db_operation( 1249): [/data/data/com.google.android.gsf/databases/talk.db,COMMIT;INSERT OR REPLACE  INTO providerSettings(value, name) VAL,252,com.google.process.gapps,100]
I/db_operation( 1377): [/data/data/com.android.providers.calendar/databases/calendar.db,COMMIT;SELECT localTimezone, minInstance, maxInstance FROM Calen,948,,100]
I/db_operation( 1377): [/data/data/com.android.providers.calendar/databases/calendar.db,COMMIT;SELECT begin-(minutes*60000) AS myAlarmTime, Instances.ev,82,,83]

It doesn't totally pin-point the offending code, but it should get us
most of the way there.  We may enhance this logging again in the
future.