Added back button when in folder view.

ui/app_list/views/app_list_folder_view.cc

Index: ui/app_list/views/app_list_folder_view.cc
diff --git a/ui/app_list/views/app_list_folder_view.cc b/ui/app_list/views/app_list_folder_view.cc
index 53f2591ba29cdda0a51b986871367f068da848d2..63c2b794ae28284568a6ca90c3d38417eb7716ca 100644
--- a/ui/app_list/views/app_list_folder_view.cc
+++ b/ui/app_list/views/app_list_folder_view.cc
@@ -111,6 +111,7 @@ void AppListFolderView::ScheduleShowHideAnimation(bool show,
       show ? kFolderTransitionInDurationMs : kFolderTransitionOutDurationMs));
 
   layer()->SetOpacity(show ? 1.0f : 0.0f);
+  app_list_main_view_->search_box_view()->SwapGoogleIconWithBackButton(show);
 }
 
 gfx::Size AppListFolderView::CalculatePreferredSize() const {