Mms: Can't display "draft" over than 6

Because we set android:ellipsize to flag end
so it is unable to display "draft" when recipients
is too long.(draft is a part of recipients content)

My solution is that set display text of combination
of recipient/draft/unread count is middle ellipsize.

CRs-Fixed: 432987

Change-Id: Ied73167e6fbb9c1c4282007c045018728d497a39