Draggable peeking/fullscreen launcher with transparent background.

ui/app_list/views/app_list_main_view_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 "ui/app_list/views/app_list_main_view.h"
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/run_loop.h"
@@ skipping 67 matching lines @@
   ~AppListMainViewTest() override {}
 
   // testing::Test overrides:
   void SetUp() override {
     views::ViewsTestBase::SetUp();
     delegate_.reset(new AppListTestViewDelegate);
 
     // In Ash, the third argument is a container aura::Window, but it is always
     // NULL on Windows, and not needed for tests. It is only used to determine
     // the scale factor for preloading icons.
-    main_view_ = new AppListMainView(delegate_.get());
+    main_view_ = new AppListMainView(delegate_.get(), nullptr);
     main_view_->SetPaintToLayer();
     main_view_->model()->SetFoldersEnabled(true);
     search_box_view_ = new SearchBoxView(main_view_, delegate_.get());
     main_view_->Init(nullptr, 0, search_box_view_);
 
     main_widget_ = new views::Widget;
     views::Widget::InitParams main_widget_params =
         CreateParams(views::Widget::InitParams::TYPE_POPUP);
     main_widget_params.bounds.set_size(main_view_->GetPreferredSize());
     main_widget_->Init(main_widget_params);
@@ skipping 343 matching lines @@
   // The app list model should remain unchanged.
   EXPECT_EQ(1, FolderViewModel()->view_size());
   EXPECT_EQ(2, RootViewModel()->view_size());
   EXPECT_EQ(folder_id, RootGridView()->GetItemViewAt(0)->item()->id());
   EXPECT_NE(nullptr,
             delegate_->GetTestModel()->FindFolderItem("single_item_folder"));
 }
 
 }  // namespace test
 }  // namespace app_list