Remove Shell::shelf()|status_area_widget()|launcher()

ash/system/tray/tray_background_view.cc

Index: ash/system/tray/tray_background_view.cc
diff --git a/ash/system/tray/tray_background_view.cc b/ash/system/tray/tray_background_view.cc
index 3886154525c69fe0a852bedb22762dd0574c6b22..c8223bea633aeca6decdfb4409c03a06a18d23e9 100644
--- a/ash/system/tray/tray_background_view.cc
+++ b/ash/system/tray/tray_background_view.cc
@@ -5,6 +5,7 @@
 #include "ash/system/tray/tray_background_view.h"
 
 #include "ash/launcher/background_animator.h"
+#include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/status_area_widget.h"
@@ -254,6 +255,11 @@ void TrayBackgroundView::SetPaintsBackground(
   hide_background_animator_.SetPaintsBackground(value, change_type);
 }
 
+ShelfLayoutManager* TrayBackgroundView::GetShelfLayoutManager() {
+  return
+      RootWindowController::ForLauncher(GetWidget()->GetNativeView())->shelf();
+}
+
 void TrayBackgroundView::SetShelfAlignment(ShelfAlignment alignment) {
   shelf_alignment_ = alignment;
   SetBorder();