Parse new config options and to batch in callback

This converts the poller's callback to batch-style pass all of the
events each time it polls rather than one-by-one. This requires a bit
more memory (up to 32kb) but will allow optimizations in the following
changes that should reduce the trace size and cpu by ~10x.

Bug: 246985031
Test: atest libnetworkstats_test
Change-Id: Ia3223ba8b27b825e2d63d6b3b8ac09b8eb17b3f8
5 files changed