Reset voicemail playback state on special expand action.

The accessibilty delegate automatically expands the call log cards when
the card is in focus. However, the voicemail state was not being reset
when this happened. Make sure to reset the voicemail playback state
when expanding the card in this manner.

Bug: 24105523
Change-Id: Ife7535980566d7b62959767d7b72df779d275270