Avoid background getTotalTimeLocked misreporting

It has been discovered that for background values of
AggregatedWakelock, Sync, Job, and partial wakelocks,
the value of getTotalTimeLocked is wrong and often very
negative. getTotalDurationMsLocked, which should provide the exact same
value in all of these cases (since background data is never pooled),
does not have this problem. So while the source of the bug is sought
out, we should use getTotalDurationMsLocked instead of getTotalTimeLocked for
these data.

Bug: 62352334
Test: cts-tradefed run cts-dev -m CtsDumpsysHostTestCases -t android.dumpsys.cts.BatteryStatsDumpsysTest
Change-Id: I78e84368615578483ab8e9e5f0ee1d067491be08