turn off sqlite WAL until bugs bug:3024421 and bug:3353077 are fixed

they are becoming pretty disruptive bugs.
many more instances of gmail crashing with locking protocol error.
and a positive identification of WAL as the problem in Music app
AND one instance of gmail crash that I know of.
who knows how many folks are NOT reporting the gmail crash.

too bad we relied on pre-released version sqlite feature
without seeing it complettly tested in the field.

not a safe feature to turn on at this point in time.
maybe more testing and debugging in Ice timeframe.

Change-Id: I283ad26ba7e1793772a372aa8e24df0cb96ce2ef