Fix DecoratedCustomViewStyle

* Fix HUN state's end margins
* Restore previous max height of collapsed state
* Restore previous behavior of hiding the progress
  bar if content is greater than ~25dp
* Remove min height which isn't necessary now that
  the largeIcon has moved up a line.
* Fix headerless title's padding with the separator.

Bug: 163626038
Test: manual
Change-Id: I1fa1efa76192f081ac801a732812eef7f5bfa536