Show incall UI correctly.

Change I39f9b042990c7c1136fd7471cd292d5a679505cc removed what we
need. In GB we explicitly used phoneIsInUse(), so using it again
would be appropriate.

Also use "inverse" color so texts should be visble at least

Change-Id: I401bcb25d1d75a4eda5c1747e724293e93d87d68
3 files changed