Transition to appropriate state after all left addresses have been cleared.

State machine will transit to RunningState directly after clearing all
left addresses even if the preconnection flag is enabled, that seems
incorrect to skip PreconnectingState. Rely on the preconnection flag
to determine which correct state should transit to.

Bug: 159109671
Test: atest NetworkStackIntegrationTests NetworkStackTests
Change-Id: I3d520a50f26ba7fac804c85c968013b2cb7cab91