Sort experimental app list search result groups.

ui/app_list/views/search_result_tile_item_list_view.cc

Index: ui/app_list/views/search_result_tile_item_list_view.cc
diff --git a/ui/app_list/views/search_result_tile_item_list_view.cc b/ui/app_list/views/search_result_tile_item_list_view.cc
index b6b680c0cf04e72002156202de2ce1e4f8872578..adcf52a03d5fd4383c80d415d8b91186a34f73d7 100644
--- a/ui/app_list/views/search_result_tile_item_list_view.cc
+++ b/ui/app_list/views/search_result_tile_item_list_view.cc
@@ -55,6 +55,10 @@ int SearchResultTileItemListView::Update() {
         i < display_results.size() ? display_results[i] : nullptr;
     tile_views_[i]->SetSearchResult(item);
   }
+
+  set_container_score(
+      display_results.empty() ? 0 : display_results.front()->relevance());
+
   return display_results.size();
 }