chromeos: Rename ash::WmShelf to Shelf

ash/app_list/app_list_presenter_delegate.h

Index: ash/app_list/app_list_presenter_delegate.h
diff --git a/ash/app_list/app_list_presenter_delegate.h b/ash/app_list/app_list_presenter_delegate.h
index 44c106cd83a30a50f5eea1b762b1a80f062a0465..feb25e27019006a75e52420affa3f4421fe637c6 100644
--- a/ash/app_list/app_list_presenter_delegate.h
+++ b/ash/app_list/app_list_presenter_delegate.h
@@ -8,7 +8,7 @@
 #include <stdint.h>
 
 #include "ash/ash_export.h"
-#include "ash/shelf/wm_shelf_observer.h"
+#include "ash/shelf/shelf_observer.h"
 #include "ash/shell_observer.h"
 #include "base/macros.h"
 #include "ui/app_list/presenter/app_list_presenter_delegate.h"
@@ -37,7 +37,7 @@ class ASH_EXPORT AppListPresenterDelegate
       public ui::EventHandler,
       public keyboard::KeyboardControllerObserver,
       public ShellObserver,
-      public WmShelfObserver {
+      public ShelfObserver {
  public:
   AppListPresenterDelegate(
       app_list::AppListPresenterImpl* presenter,
@@ -69,7 +69,7 @@ class ASH_EXPORT AppListPresenterDelegate
   // ShellObserver overrides:
   void OnOverviewModeStarting() override;
 
-  // WmShelfObserver overrides:
+  // ShelfObserver overrides:
   void OnShelfIconPositionsChanged() override;
 
   // Whether the app list is visible (or in the process of being shown).