Moves TransientWindowClient to ui/aura/client and adds observer

ui/views/test/test_views_delegate.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_VIEWS_TEST_TEST_VIEWS_DELEGATE_H_
 #define UI_VIEWS_TEST_TEST_VIEWS_DELEGATE_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "ui/views/views_delegate.h"
 
-namespace wm {
-class WMState;
-}
-
 namespace views {
 
 class TestViewsDelegate : public ViewsDelegate {
  public:
   TestViewsDelegate();
   ~TestViewsDelegate() override;
 
   // If set to |true|, forces widgets that do not provide a native widget to use
   // DesktopNativeWidgetAura instead of whatever the default native widget would
   // be. This has no effect on ChromeOS.
@@ skipping 16 matching lines @@
 #endif
   void OnBeforeWidgetInit(Widget::InitParams* params,
                           internal::NativeWidgetDelegate* delegate) override;
   ui::ContextFactory* GetContextFactory() override;
 
  private:
   ui::ContextFactory* context_factory_;
   bool use_desktop_native_widgets_;
   bool use_transparent_windows_;
 
-#if defined(USE_AURA)
-  std::unique_ptr<wm::WMState> wm_state_;
-#endif
-
   DISALLOW_COPY_AND_ASSIGN(TestViewsDelegate);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_TEST_TEST_VIEWS_DELEGATE_H_