Makes Panel related classes use ash/wm/common types

ash/accelerators/accelerator_controller_unittest.cc

Index: ash/accelerators/accelerator_controller_unittest.cc
diff --git a/ash/accelerators/accelerator_controller_unittest.cc b/ash/accelerators/accelerator_controller_unittest.cc
index 00625c5b6bce51f238364a5542f7eb122d61e352..a657b7fbde8cbb8e49bf6c67cfa4ab796500a5a7 100644
--- a/ash/accelerators/accelerator_controller_unittest.cc
+++ b/ash/accelerators/accelerator_controller_unittest.cc
@@ -278,9 +278,8 @@ class AcceleratorControllerTest : public test::AshTestBase {
     test::TestShelfDelegate* shelf_delegate =
       test::TestShelfDelegate::instance();
     shelf_delegate->AddShelfItem(window);
-    PanelLayoutManager* manager = static_cast<PanelLayoutManager*>(
-        Shell::GetContainer(window->GetRootWindow(),
-                            kShellWindowId_PanelContainer)->layout_manager());
+    PanelLayoutManager* manager =
+        PanelLayoutManager::Get(wm::WmWindowAura::Get(window));
     manager->Relayout();
     return window;
   }