Turn vibrator off explicitly on waveforms when amplitude is zero

This makes sure the drive will be off for the period of time described in the waveform pattern with amplitude = 0.

Bug: 172492945
Test: atest FrameworksServicesTests:VibratorServiceTest
Change-Id: I753e4846fce3066b78e818afa5c794b113244ab0
2 files changed