Regression from commit 6d64d2f3 (Minor
refactoring and cleanup of Scheduler and Timer., 2015-07-19), the old
Timer::ImplStartTimer() used to set nMS to at least 1, but the new
Scheduler::ImplStartTimer() didn't do that.

With this, JunitTest_sw_unoapi_3 no longer hangs for me.

Change-Id: I16ad360f1e5430cde7ec8b28e8c2620d260c9ec0