3f3913550c
Implements read/write of network stats using AtomicFile, along with magic number and versioning. Stores in "/data/system/netstats.bin" for now. Tests to verify that stats are persisted across a simulated reboot, and to verify that TEMPLATE_WIFI is working. Fixed bug where kernel counters rolling backwards would cause negative stats to be recorded; now we clamp deltas at 0. Change-Id: I53bce26fc8fd3f4ab1e34ce135d302edfa34db34