ash: Move ShelfWidget ownership to WmShelf and refactor access to it

ash/wm/workspace_controller_unittest.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/wm/workspace_controller.h"
 
 #include <map>
 
 #include "ash/aura/wm_window_aura.h"
 #include "ash/common/shelf/shelf_layout_manager.h"
 #include "ash/common/shelf/shelf_widget.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/system/status_area_widget.h"
 #include "ash/common/wm/panels/panel_layout_manager.h"
 #include "ash/common/wm/window_state.h"
 #include "ash/common/wm/workspace/workspace_window_resizer.h"
-#include "ash/root_window_controller.h"
 #include "ash/screen_util.h"
 #include "ash/shell.h"
 #include "ash/test/ash_md_test_base.h"
 #include "ash/test/shell_test_api.h"
 #include "ash/test/test_shelf_delegate.h"
 #include "ash/wm/window_state_aura.h"
 #include "ash/wm/window_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/test/test_window_delegate.h"
@@ skipping 106 matching lines @@
     return Shell::GetContainer(Shell::GetPrimaryRootWindow(),
                                kShellWindowId_DefaultContainer);
   }
 
   gfx::Rect GetFullscreenBounds(aura::Window* window) {
     return display::Screen::GetScreen()
         ->GetDisplayNearestWindow(window)
         .bounds();
   }
 
-  ShelfWidget* shelf_widget() {
-    return Shell::GetPrimaryRootWindowController()->shelf_widget();
-  }
+  ShelfWidget* shelf_widget() { return GetPrimaryShelf()->shelf_widget(); }
 
   ShelfLayoutManager* shelf_layout_manager() {
-    return Shell::GetPrimaryRootWindowController()->GetShelfLayoutManager();
+    return GetPrimaryShelf()->shelf_layout_manager();
   }
 
   bool GetWindowOverlapsShelf() {
     return shelf_layout_manager()->window_overlaps_shelf();
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WorkspaceControllerTest);
 };
 
@@ skipping 1455 matching lines @@
                          ui::EventTimeForNow());
     target = targeter->FindTargetForEvent(root, &touch);
     if (points[i].is_target_hit)
       EXPECT_EQ(window.get(), target);
     else
       EXPECT_NE(window.get(), target);
   }
 }
 
 }  // namespace ash