Fix voicemail tab items reading "speed dial" when selected.

The voicemail entries were reading "speed dial" because the focus would go
to the newly added "speed dial" tab since the tabs are all removed and
readded when the tab info changes. Change the logic so that only the
voicemail tab is changed when needed.
The voicemail entry reads "seek playback" instead of the information
about the voicemail because of custom expand logic for accessibilty.
Change it so that only the call log items are expanded when selected
(it is more important to be able to discover the overflow options).
Also change content description text because it was too long and confusing.

Bug: 25124120
Change-Id: I64c1b27d8c0db57525f7f4ada59655e9f8352245