Update DataTables only after previous call is done

When the update is always made at a set interval, the next update could
be called before the previous one has completed. Data inconsistencies
could arise from changes being made out of order in the updates. Move
the code to call the next update to the "complete" function to make sure
the previous call has finished before starting the next one.

Change-Id: I946912a30934e8d25f83fadaef7c2b8b6db269b2
Closes-Bug: #1231751
Merge "Update DataTables only after previous call is done"