Rebind recycler views if launcher activity restarted

Bug: 185038312
Test: manual
TL;DR;;
What was attempted but was too much refactoring of the code.

Failed attempt #1: try re triggering the search.
This was not trivial as SearchSession object is yet created.

Failed attempt #2: Restoring AdapterItems in AlphabeticalAppsList
This meant AdapterItems class and also it's children
had to extend Parceleable object.

Ultimate fix:
Original issue of dupe view id among slice and work recyclerview
should be fixed. And restoring should just work.

Change-Id: I1bddd6aa5bc736ade3b02f69aa947d64cfa467d6

src/com/android/launcher3/allapps/AllAppsRecyclerView.java

@@ -40,6 +40,7 @@ import com.android.launcher3.BaseRecyclerView;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.R;
+import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.logging.StatsLogManager;
 import com.android.launcher3.views.ActivityContext;
 import com.android.launcher3.views.RecyclerViewFastScroller;
@@ -166,7 +167,7 @@ public class AllAppsRecyclerView extends BaseRecyclerView {
         // Always scroll the view to the top so the user can see the changed results
         scrollToTop();
 
-        if (mApps.hasNoFilteredResults()) {
+        if (mApps.hasNoFilteredResults() && !FeatureFlags.ENABLE_DEVICE_SEARCH.get()) {
             if (mEmptySearchBackground == null) {
                 mEmptySearchBackground = new AllAppsBackgroundDrawable(getContext());
                 mEmptySearchBackground.setAlpha(0);