DesktopAura: Track windows "owned" via the DesktopWindowTreeHost

ui/views/widget/widget_unittest.cc

Index: ui/views/widget/widget_unittest.cc
diff --git a/ui/views/widget/widget_unittest.cc b/ui/views/widget/widget_unittest.cc
index 52845e5ed925fc9141065f1f52e2ac2e7a8ccfc2..f2345d96ad8917b14e5e796bdb0d900ade440187 100644
--- a/ui/views/widget/widget_unittest.cc
+++ b/ui/views/widget/widget_unittest.cc
@@ -3090,6 +3090,42 @@ TEST_F(WidgetChildDestructionTest, DestroyChildWidgetsInOrder) {
   RunDestroyChildWidgetsTest(false, false);
 }
 
+// Ensure that if a Widget is created with parent and is created using a
+// top-level Widget, then it is destroyed when the parent Widget goes away.
+TEST_F(WidgetTest, TopLevelChildWindowDestroyedWithParent) {
+  Widget::InitParams params = CreateParams(Widget::InitParams::TYPE_WINDOW);
+  params.bounds = gfx::Rect(100, 100, 100, 100);
+
+  Widget* parent_widget = new Widget();  // Owned by Native Widget.
+  bool parent_destroyed = false;
+  params.native_widget = CreatePlatformDesktopNativeWidgetImpl(
+      params, parent_widget, &parent_destroyed);
+  parent_widget->Init(params);
+  parent_widget->Show();
+
+  Widget* child_widget = new Widget();
+  bool child_destroyed = false;
+  params.parent = parent_widget->GetNativeView();
+  params.native_widget = CreatePlatformDesktopNativeWidgetImpl(
+      params, child_widget, &child_destroyed);
+  child_widget->Init(params);
+  child_widget->Show();
+
+  // |child_widget| is destroyed when |parent_widget| goes away, so it should be
+  // considered "owned".
+  std::set<Widget*> owned_widgets;
+  Widget::GetAllOwnedWidgets(parent_widget->GetNativeView(), &owned_widgets);
+  EXPECT_EQ(1u, owned_widgets.count(child_widget));

[tapted, 2017/01/23 10:52:55]

This fails on desktop linux and windows (and mus) without the
desktop_window_host_foo changes.

+
+  // Trigger child destruction via a call to one of the following on the parent
+  // window: DesktopWindowTreeHostX11::CloseNow(), ::DestroyWindow(),
+  // DesktopWindowTreeHostMus::CloseNow(), or BridgedNativeWidget::
+  // OnWindowWillClose().
+  parent_widget->CloseNow();
+  EXPECT_TRUE(parent_destroyed);
+  EXPECT_TRUE(child_destroyed);

[tapted, 2017/01/23 10:52:55]

This already passes - it's just to assert that the child is actually owned.

+}
+
 // Verifies nativeview visbility matches that of Widget visibility when
 // SetFullscreen is invoked.
 TEST_F(WidgetTest, FullscreenStatePropagated) {