Moves maintaining ShellObservers back to Shell

ash/common/test/test_shelf_delegate.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/common/test/test_shelf_delegate.h"
 
 #include <utility>
 
 #include "ash/common/shelf/shelf_model.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shell_observer.h"
 #include "ash/common/test/test_shelf_item_delegate.h"
 #include "ash/common/wm_shell.h"
 #include "ash/common/wm_window.h"
 #include "ash/root_window_controller.h"
+#include "ash/shell.h"
 #include "ash/wm/window_properties.h"
 #include "base/memory/ptr_util.h"
 #include "ui/aura/window.h"
 
 namespace ash {
 namespace test {
 
 TestShelfDelegate* TestShelfDelegate::instance_ = nullptr;
 
 // A ShellObserver that sets the shelf alignment and auto hide behavior when the
 // shelf is created, to simulate ChromeLauncherController's behavior.
 class ShelfInitializer : public ShellObserver {
  public:
-  ShelfInitializer() { WmShell::Get()->AddShellObserver(this); }
-  ~ShelfInitializer() override { WmShell::Get()->RemoveShellObserver(this); }
+  ShelfInitializer() { Shell::GetInstance()->AddShellObserver(this); }
+  ~ShelfInitializer() override {
+    Shell::GetInstance()->RemoveShellObserver(this);
+  }
 
   // ShellObserver:
   void OnShelfCreatedForRootWindow(WmWindow* root_window) override {
     WmShelf* shelf = root_window->GetRootWindowController()->GetShelf();
     // Do not override the custom initialization performed by some unit tests.
     if (shelf->alignment() == SHELF_ALIGNMENT_BOTTOM_LOCKED &&
         shelf->auto_hide_behavior() == SHELF_AUTO_HIDE_ALWAYS_HIDDEN) {
       shelf->SetAlignment(SHELF_ALIGNMENT_BOTTOM);
       shelf->SetAutoHideBehavior(SHELF_AUTO_HIDE_BEHAVIOR_NEVER);
       shelf->UpdateVisibilityState();
@@ skipping 112 matching lines @@
                                                  const std::string& app_id) {
   shelf_id_to_app_id_map_[shelf_id] = app_id;
 }
 
 void TestShelfDelegate::RemoveShelfIDToAppIDMapping(ShelfID shelf_id) {
   shelf_id_to_app_id_map_.erase(shelf_id);
 }
 
 }  // namespace test
 }  // namespace ash