logcat: test: inject() tuning

Add a hidden -v nsec flag to logcat (actually logprint in liblog.so)
so that we can do more exacting tests of logcat.tail_time.  Halve the
spam pressure of logcat.tail_* in inject() routine, and give us a few
more retries at the higher counts.  Add instrumentation to
logcat.logrotate failures.  Add inject for logcat.year test.

Test: gTest logcat-unit-tests
Bug: 34454772
Change-Id: If6f3bd21892c8a2b9ccee8c8bbf592a1ae0b2a57