Work on issue #70859548: Reduce amount of time spent collecting pss data

This slightly reduces the frequency we collect pss data, adjusting
some timings and adding back separate timings for when the device
is asleep.  (Though note that the "same asleep" timings are currently
the same as "same awake," because those are already pretty infrequent.)

Also add some statistics to procstats to keep track of how many
pss samples have been taken, generally why, and how long they took

Bug: 70859548
Test: manual
Change-Id: If3c6cbd4ab045d2e4c00b48fe4257c4ec5ae3f33