Fix ash shell child modal window example

Attempting to use this example crashes otherwise:
[233814:233814:0703/151833.248652:FATAL:native_widget_aura.cc(151)] Check failed: params.parent || params.context.
#0 0x7f45424a2f7c base::debug::StackTrace::StackTrace()
#1 0x7f45423f23bb logging::LogMessage::~LogMessage()
#2 0x7f453db8604b views::NativeWidgetAura::InitNativeWidget()
#3 0x7f453db68157 views::Widget::Init()
#4 0x0000004e76bd ash::TestChildModalParent::TestChildModalParent()
#5 0x0000004e74ee ash::TestChildModalParent::Create()
#6 0x7f453daefbed views::Button::OnMouseReleased()

Bug: NONE
Test: No ash_shell_with_content crash showing child modal window.
Change-Id: Ic6a2382676d54ea47fd1a6a70b0209c26fd3d87f
Reviewed-on: https://chromium-review.googlesource.com/1125294Reviewed-by: James Cook <jamescook@chromium.org>
Commit-Queue: Michael Wasserman <msw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572414}

ash/shell/window_type_launcher.cc

@@ -285,7 +285,7 @@ void WindowTypeLauncher::ButtonPressed(views::Button* sender,
     ModalWindow::OpenModalWindow(GetWidget()->GetNativeView(),
                                  ui::MODAL_TYPE_WINDOW);
   } else if (sender == child_modal_button_) {
-    TestChildModalParent::Create();
+    TestChildModalParent::Create(GetWidget()->GetNativeView()->GetRootWindow());
   } else if (sender == transient_button_) {
     NonModalTransient::OpenNonModalTransient(GetWidget()->GetNativeView());
   } else if (sender == show_hide_window_button_) {

ash/wm/test_child_modal_parent.cc

@@ -96,14 +96,14 @@ ui::ModalType ChildModalWindow::GetModalType() const {
 }
 
 // static
-void TestChildModalParent::Create() {
+void TestChildModalParent::Create(aura::Window* context) {
   Widget::CreateWindowWithContextAndBounds(
-      new TestChildModalParent(), /*context=*/nullptr,
+      new TestChildModalParent(context), context,
       gfx::Rect(kWindowLeft, kWindowTop, kWindowWidth, kWindowHeight))
       ->Show();
 }
 
-TestChildModalParent::TestChildModalParent()
+TestChildModalParent::TestChildModalParent(aura::Window* context)
     : widget_(std::make_unique<Widget>()),
       button_(new views::LabelButton(
           this,
@@ -113,6 +113,7 @@ TestChildModalParent::TestChildModalParent()
       child_(nullptr) {
   Widget::InitParams params(Widget::InitParams::TYPE_CONTROL);
   params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+  params.context = context;
   widget_->Init(params);
   widget_->GetRootView()->SetBackground(
       views::CreateSolidBackground(kModalParentColor));

ash/wm/test_child_modal_parent.h

@@ -28,9 +28,9 @@ class TestChildModalParent : public views::WidgetDelegateView,
                              public views::WidgetObserver {
  public:
   // Creates the test window.
-  static void Create();
+  static void Create(aura::Window* context);
 
-  TestChildModalParent();
+  explicit TestChildModalParent(aura::Window* context);
   ~TestChildModalParent() override;
 
   void ShowChild();

ash/wm/window_modality_controller_unittest.cc

@@ -253,7 +253,7 @@ TEST_F(WindowModalityControllerTest, GetModalTransient) {
 
   aura::Window* wt;
   wt = ::wm::GetModalTransient(w1.get());
-  ASSERT_EQ(static_cast<aura::Window*>(NULL), wt);
+  ASSERT_EQ(nullptr, wt);
 
   // Parent w2 to w1. It should get parented to the parent of w1.
   ::wm::AddTransientChild(w1.get(), w2.get());
@@ -262,12 +262,12 @@ TEST_F(WindowModalityControllerTest, GetModalTransient) {
 
   // Request the modal transient window for w1, it should be w2.
   wt = ::wm::GetModalTransient(w1.get());
-  ASSERT_NE(static_cast<aura::Window*>(NULL), wt);
+  ASSERT_NE(nullptr, wt);
   EXPECT_EQ(-2, wt->id());
 
   // Request the modal transient window for w11, it should also be w2.
   wt = ::wm::GetModalTransient(w11.get());
-  ASSERT_NE(static_cast<aura::Window*>(NULL), wt);
+  ASSERT_NE(nullptr, wt);
   EXPECT_EQ(-2, wt->id());
 }
 
@@ -463,7 +463,7 @@ TEST_F(WindowModalityControllerTest, TouchEvent) {
 //   |child| window.
 // - Focus should follow the active window.
 TEST_F(WindowModalityControllerTest, ChildModal) {
-  TestChildModalParent* delegate = new TestChildModalParent();
+  TestChildModalParent* delegate = new TestChildModalParent(nullptr);
   views::Widget* widget = views::Widget::CreateWindowWithContextAndBounds(
       delegate, nullptr /* context */, gfx::Rect(0, 0, 400, 400));
   widget->Show();
@@ -472,7 +472,7 @@ TEST_F(WindowModalityControllerTest, ChildModal) {
   EXPECT_TRUE(wm::IsActiveWindow(parent));
 
   aura::Window* modal_parent = delegate->GetModalParent();
-  EXPECT_NE(static_cast<aura::Window*>(NULL), modal_parent);
+  EXPECT_NE(nullptr, modal_parent);
   EXPECT_NE(parent, modal_parent);
   EXPECT_FALSE(wm::IsActiveWindow(modal_parent));
 
@@ -522,7 +522,7 @@ TEST_F(WindowModalityControllerTest, ChildModal) {
 // Same as |ChildModal| test, but using |EventGenerator| rather than bypassing
 // it by calling |ActivateWindow|.
 TEST_F(WindowModalityControllerTest, ChildModalEventGenerator) {
-  TestChildModalParent* delegate = new TestChildModalParent();
+  TestChildModalParent* delegate = new TestChildModalParent(nullptr);
   views::Widget* widget = views::Widget::CreateWindowWithContextAndBounds(
       delegate, nullptr /* context */, gfx::Rect(0, 0, 400, 400));
   widget->Show();
@@ -531,13 +531,13 @@ TEST_F(WindowModalityControllerTest, ChildModalEventGenerator) {
   EXPECT_TRUE(wm::IsActiveWindow(parent));
 
   aura::Window* modal_parent = delegate->GetModalParent();
-  EXPECT_NE(static_cast<aura::Window*>(NULL), modal_parent);
+  EXPECT_NE(nullptr, modal_parent);
   EXPECT_NE(parent, modal_parent);
   EXPECT_FALSE(wm::IsActiveWindow(modal_parent));
 
   delegate->ShowChild();
   aura::Window* child = delegate->GetChild();
-  EXPECT_NE(static_cast<aura::Window*>(NULL), child);
+  EXPECT_NE(nullptr, child);
 
   EXPECT_TRUE(wm::IsActiveWindow(child));
   EXPECT_FALSE(wm::IsActiveWindow(modal_parent));