Lock screen preview.

Adds code on the system UI side that renders a preview of the lock
screen. This is done through the content provider, which receives a
handle to a SurfaceView from wallpaper picker, where the UI is actually
shown to the user.

There are several changes here, following the path of the code, they
are:
1. KeyguardQuickAffordanceProvider can handle the "call" from wallpaper
   picker and delegates the rendering to the preview system
2. The preview system starts with KeyguardRemotePreviewManager which is
   responsible for driving the lifecycle of the rendering as the
   connection to the remote SurfaceView is established or torn down
3. The preview system continues with the KeyguardPreviewRenderer which
   builds the view hierarchy and hooks up each view to its appropriate
   view-binder or view-controller
4. For quick affordances, we are making a couple of minor changes to the
   view-binder, view-model, and interactor to allow for them to run in
   "preview" mode where different rules apply: no clicks allowed, the
   affordances are ever-visible (as opposed to only when the lock screen
   is shown), etc.

Bug: 261362750
Test: unit tests created/updated, manually verified in the shortcuts
settings screen

Change-Id: I5d1c51dacbedf0a7a1fb3ec742244141a2fe8a32