Moves TransientWindowClient to ui/aura/client and adds observer

ui/wm/core/shadow_controller_unittest.cc

 // 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.
 
 #include "ui/wm/core/shadow_controller.h"
 
 #include <algorithm>
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/window_parenting_client.h"
 #include "ui/aura/test/aura_test_base.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/compositor/layer.h"
 #include "ui/wm/core/default_activation_client.h"
 #include "ui/wm/core/shadow.h"
 #include "ui/wm/core/shadow_types.h"
 #include "ui/wm/core/window_util.h"
-#include "ui/wm/core/wm_state.h"
 #include "ui/wm/public/activation_client.h"
 
 namespace wm {
 
 class ShadowControllerTest : public aura::test::AuraTestBase {
  public:
   ShadowControllerTest() {}
   ~ShadowControllerTest() override {}
 
   void SetUp() override {
-    wm_state_.reset(new wm::WMState);
     AuraTestBase::SetUp();
     new wm::DefaultActivationClient(root_window());
     aura::client::ActivationClient* activation_client =
         aura::client::GetActivationClient(root_window());
     shadow_controller_.reset(new ShadowController(activation_client));
   }
   void TearDown() override {
     shadow_controller_.reset();
     AuraTestBase::TearDown();
-    wm_state_.reset();
   }
 
  protected:
   ShadowController* shadow_controller() { return shadow_controller_.get(); }
 
   void ActivateWindow(aura::Window* window) {
     DCHECK(window);
     DCHECK(window->GetRootWindow());
     aura::client::GetActivationClient(window->GetRootWindow())->ActivateWindow(
         window);
   }
 
  private:
   std::unique_ptr<ShadowController> shadow_controller_;
-  std::unique_ptr<wm::WMState> wm_state_;
 
   DISALLOW_COPY_AND_ASSIGN(ShadowControllerTest);
 };
 
 // Tests that various methods in Window update the Shadow object as expected.
 TEST_F(ShadowControllerTest, Shadow) {
   std::unique_ptr<aura::Window> window(new aura::Window(NULL));
   window->SetType(ui::wm::WINDOW_TYPE_NORMAL);
   window->Init(ui::LAYER_TEXTURED);
   ParentWindow(window.get());
@@ skipping 154 matching lines @@
   AddTransientChild(window1.get(), window2.get());
   aura::client::SetHideOnDeactivate(window2.get(), true);
   window2->Show();
   ActivateWindow(window2.get());
 
   // window1 is now inactive, but its shadow should still appear active.
   EXPECT_EQ(Shadow::STYLE_ACTIVE, shadow1->style());
 }
 
 }  // namespace wm