mash: Support ShelfModel access in Chrome.

chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
index 2ca87d90bc1d66025ead46c8e7a48d8765abc503..dc22ba1304e34b1b2aa5c86612ceaf935360c2c4 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_browsertest.cc
@@ -2502,3 +2502,13 @@ IN_PROC_BROWSER_TEST_F(ShelfAppBrowserTest,
   ASSERT_FALSE(
       IsItemPresentInMenu(menu2.get(), LauncherContextMenu::MENU_CLOSE));
 }
+
+// Chrome's ShelfModel should have AppList and browser items and delegates.
+IN_PROC_BROWSER_TEST_F(ShelfAppBrowserTest, ShelfModelInitialization) {
+  ash::ShelfModel* model = controller_->shelf_model();
+  EXPECT_EQ(2, model->item_count());
+  EXPECT_EQ(ash::kAppListId, model->items()[0].id.app_id);
+  EXPECT_TRUE(model->GetShelfItemDelegate(ash::kAppListId));
+  EXPECT_EQ(extension_misc::kChromeAppId, model->items()[1].id.app_id);
+  EXPECT_TRUE(model->GetShelfItemDelegate(extension_misc::kChromeAppId));
+}