Merge changes Ic590c230,Ibd4be82b

* changes:
  logd: liblog benchmark check BM_log_overhead regression
  liblog: benchmark add BM_log_event_overhead_42 for a well known tag
tree: f6bb02b177d60c7976647fefc1c8a16afe1546b9
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/