Moves TransientWindowClient to ui/aura/client and adds observer

ui/aura/test/aura_test_helper.h

 // Copyright (c) 2012 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.
 
 #ifndef UI_AURA_TEST_AURA_TEST_HELPER_H_
 #define UI_AURA_TEST_AURA_TEST_HELPER_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tree_host.h"
 
 namespace base {
 class MessageLoopForUI;
 }
 
 namespace ui {
 class ContextFactory;
 class InputMethod;
 class ScopedAnimationDurationScaleMode;
 }
 
+namespace wm {
+class WMState;
+}
+
 namespace aura {
+class Env;
 class TestScreen;
 class TestWindowTree;
 class TestWindowTreeClientSetup;
 class Window;
 class WindowPort;
 class WindowManagerDelegate;
 class WindowTreeClient;
 class WindowTreeClientDelegate;
 
 namespace client {
@@ skipping 41 matching lines @@
   Env::WindowPortFactory InitMus();
 
   std::unique_ptr<WindowPort> CreateWindowPortMus(Window* window);
 
   base::MessageLoopForUI* message_loop_;
   bool use_mus_ = false;
   bool setup_called_;
   bool teardown_called_;
   std::unique_ptr<TestWindowTreeClientSetup> window_tree_client_setup_;
   std::unique_ptr<aura::Env> env_;
+  std::unique_ptr<wm::WMState> wm_state_;
   std::unique_ptr<WindowTreeHost> host_;
   std::unique_ptr<TestWindowParentingClient> parenting_client_;
   std::unique_ptr<client::DefaultCaptureClient> capture_client_;
   std::unique_ptr<client::FocusClient> focus_client_;
   std::unique_ptr<TestScreen> test_screen_;
   std::unique_ptr<ui::ScopedAnimationDurationScaleMode> zero_duration_mode_;
   WindowTreeClientDelegate* window_tree_delegate_ = nullptr;
   WindowManagerDelegate* window_manager_delegate_ = nullptr;
 
   DISALLOW_COPY_AND_ASSIGN(AuraTestHelper);
 };
 
 }  // namespace test
 }  // namespace aura
 
 #endif  // UI_AURA_TEST_AURA_TEST_HELPER_H_