Add WorkspaceRevealAnim, successor to StaggeredWorkspaceAnim.

- Added support for widgets for the new close animation.
- This anim is used with the new app close.
- This anim is not compataible with the old app close, so we need to
  keep StaggeredWorkspaceAnim in case we turn the app close flag off.

- We will also use this anim in the lockscreen to launcher anim, will
  connect them in a follow up CL.

Bug: 188413065
Bug: 173107751
Test: manual
Change-Id: Icab3fd700f2c268bb1c4509a37466e4e6748f789