Delete stats_event_list refs from statsd src

This breaks LogEvent::writeBytes, but that function is only called from
test code (and those tests are about to be broken soon anyways).

Test: m statsd
Test: m statsd_test
Bug: 145573568

Change-Id: Ic2d2e7c80d25fa93269e3432dbe58dffbd80dfd4
2 files changed