Assert mean and stdev of update deltas

Assert mean and standard deviation of location update deltas in GPS CTS
test, instead of individual values of deltas. This gives more
flexibility to implementations that cannot respect an exect schedule.
This still prevents implementations from computing too many fixes and
using too much battery.

Change-Id: Ic889c567bc7262073da87eba493ffee0f9e68b4d
2 files changed