Add and separate Account Item View

Move account out of FolderItemView and simplify
some of the key functionality (removing params
and instance vars).

Fix the multi-select bug as well by disabling
state_activated for the account_item style.

Changed the header as well to make the style
different for currently selected account.

Bug: 8440682
Change-Id: I55c55e403bc64733b5924f95f423fd1097c4dc16
7 files changed