Display proper incoming call in Answer Fragment.

- In case of two incoming calls, display the call
in answer fragment which was last shown in HUN when
HUN is tapped.

- In case of multiple held calls, fix displaying
number instead of name for a saved contact in held
call banner when next button in banner is clicked.

Change-Id: Id7044bc36ed4ede6f5a0156bb167be633f31b67e
CRs-Fixed: 3076144
5 files changed