Fixed various conversation layout appearences

Previously the layout would break if the developer
specified empty names or no avatars. Similarly if
a developer specified a conversationtitle in a
one to one chat, it would break badly as well.

Bug: 150905003
Test: create various edge case chats and observe the layout
Change-Id: If904c85e6d582b4735eb928d66749a7863fbbc06
7 files changed