Moves app_list() and related functions from Shell to WmShell

ash/common/shelf/app_list_shelf_item_delegate.cc

Index: ash/common/shelf/app_list_shelf_item_delegate.cc
diff --git a/ash/common/shelf/app_list_shelf_item_delegate.cc b/ash/common/shelf/app_list_shelf_item_delegate.cc
index bc9b724f56e3494511f10c28b5184561c5a3bf9b..42bf94d7f0f489b616705dc62d64e1ba31c42e1f 100644
--- a/ash/common/shelf/app_list_shelf_item_delegate.cc
+++ b/ash/common/shelf/app_list_shelf_item_delegate.cc
@@ -5,7 +5,7 @@
 #include "ash/common/shelf/app_list_shelf_item_delegate.h"
 
 #include "ash/common/shelf/shelf_model.h"
-#include "ash/common/wm_shell.h"
+#include "ash/shell.h"
 #include "ash/strings/grit/ash_strings.h"
 #include "base/memory/ptr_util.h"
 #include "ui/app_list/app_list_switches.h"
@@ -37,7 +37,7 @@ void AppListShelfItemDelegate::ItemSelected(
     int64_t display_id,
     ShelfLaunchSource source,
     const ItemSelectedCallback& callback) {
-  WmShell::Get()->ToggleAppList();
+  Shell::Get()->ToggleAppList();
   callback.Run(SHELF_ACTION_APP_LIST_SHOWN, base::nullopt);
 }