Remove suggestion UI v1 codes.

- remove the check for feature flag for suggestion UI v2 and switch to
use the v2 codes.
- remove all code related to v1 of suggestion UI

Fixes: 70573674
Test: make RunSettingsRoboTests

Change-Id: I99ab318c1c0192508a9c5e9e708e86319120d55b

src/com/android/settings/dashboard/DashboardFeatureProvider.java

@@ -90,9 +90,4 @@ public interface DashboardFeatureProvider {
      */
     void openTileIntent(Activity activity, Tile tile);
 
-    /**
-     * Whether or not we should use the v2 of suggestions UI.
-     */
-    boolean useSuggestionUiV2();
-
 }