interval=0 causes infinite loop (reschedules at same time, never breaks).
interval=1 with millis() doesn't work (real time doesn't advance fast
enough between inner iterations for intervals to re-fire).
Solution: use interval=1 with monotonically increasing fake time (now++)
and disable WarnIfComponentBlockingGuard at compile time via
-DWARN_IF_BLOCKING_OVER_MS=UINT32_MAX in benchmark build flags. This
prevents the guard's (millis() - started_) underflow when fake time
exceeds real millis().
J. Nick Koston
ec60e2c228