Bug 1068051 - Add high-res device drawables. r=trivial
Bug 1068051 - Post: Remove unnecessary style. r=trivial

This layout is not used by the Share Overlay system.  It is used only by
the Sync Send Tab Activity, which lives in android-sync.  Mixing the
styles in this way ties the repositories together in a way we don't
want.
Bug 1068365 - Part 1: Make collapsed remote clients look grayed out. r=rnewman

There are two major ways to achieve this.  One is to painstakingly
update UI elements every time we fetch a group.  I've done that.  The
other is to maintain expanded and collapsed layouts.  I went quite far
down that path; doing it is less pleasant than I expected for the
following reasons:

1) we have to update the view graphics depending on the client device
type anyway;

2) Android's view recycling does not track the expanded/collapsed state,
so we either manage the expanded states and have multiple group
types (see modern versions of SimpleExpandableListAdapter) or we
duplicate the work we're doing here;

3) our expanded and collapsed layouts are so similar that duplicating
them is worse than futzing with them in this manner.
Bug 1068365 - Part 2: Correct remote clients expanded/collapsed icons. r=antlam
Bug 1068366 - Update "Hidden devices" footer visual style in Remote Tabs home panel. r=trivial

The background colour was already correct.  This updates the text color
to match the mock, and adds a background selector that styles the footer
correctly when it is tapped.