Remove useless delay when no running time entries.
Remove useless delay when no running time entries.

When there were no running time entries the EnsureLiveDuration would
still wait 500ms, during which time there could've been added some new
running time entries, but were in fact ignored due to that delay.

peeedge/mobile,peeedge/mobile,eatskolnikov/mobile,ZhangLeiCharles/mobile,eatskolnikov/mobile,ZhangLeiCharles/mobile,eatskolnikov/mobile,masterrr/mobile,masterrr/mobile