Reload homepage cards when necessary

Many users leave Settings app by pressing Home key, but Settings remains
in the same card status and doesn't update when users come back, which
may lead to a bad UX.

This change reloads cards and resets the UI session for some events,
including home key, recent app key, and screen off.

Fixes: 151789260
Test: robotest
Change-Id: Idb575cef4a58894984cb42238d7b3b43c49389a3

src/com/android/settings/homepage/contextualcards/ContextualCardsAdapter.java

@@ -135,8 +135,6 @@ public class ContextualCardsAdapter extends RecyclerView.Adapter<RecyclerView.Vi
             // Adding items to empty list, should animate.
             mRecyclerView.scheduleLayoutAnimation();
         }
-
-        //TODO(b/119465242): flickering conditional cards after collapsing/expanding
     }
 
     @Override