Add better a11y support in QS

* Add ACTION_PAGE_LEFT/RIGHT to PagedTileLayout and proper focus after
  changing pages.
* Add CollectionInfo to TileLayout and CollectionItemInfo to
  QSTileViewImpl to indicate the position of the currently focused tile.
* Properly use ACTION_COLLAPSE/EXPAND in QSPanel/QuickQSPanel so the
  proper announcement is made, as well as the proper action is provided
  in the contextual menu.

Test: manual
Test: atest com.android.systemui.qs
Bug: 204726862
Change-Id: I9bb085002c99e75ab0bb91f287ded62793b932bb