Notify WidgetRemovalsObserver when RootView is removed

ui/views/widget/widget_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 <algorithm>
 #include <memory>
 #include <set>
 
 #include "base/bind.h"
 #include "base/macros.h"
@@ skipping 3631 matching lines @@
   EXPECT_TRUE(removals_observer.DidRemoveView(parent));
   EXPECT_FALSE(removals_observer.DidRemoveView(child));
 
   // Calling RemoveChildView() doesn't delete the view, but deleting
   // |parent| will automatically delete |child|.
   delete parent;
 
   widget->RemoveRemovalsObserver(&removals_observer);
 }
 
+// Test that WidgetRemovalsObserver::OnWillRemoveView is called when deleting
+// the root view.
+TEST_F(WidgetTest, WidgetRemovalsObserverCalledWhenRemovingRootView) {
+  WidgetAutoclosePtr widget(CreateTopLevelPlatformWidget());
+  TestWidgetRemovalsObserver removals_observer;
+  widget->AddRemovalsObserver(&removals_observer);
+  views::View* root_view = widget->GetRootView();
+
+  widget.reset();
+  EXPECT_TRUE(removals_observer.DidRemoveView(root_view));
+}
+
 // Test that WidgetRemovalsObserver::OnWillRemoveView is called when moving
 // a view from one widget to another, but not when moving a view within
 // the same widget.
 TEST_F(WidgetTest, WidgetRemovalsObserverCalledWhenMovingBetweenWidgets) {
   WidgetAutoclosePtr widget(CreateTopLevelPlatformWidget());
   TestWidgetRemovalsObserver removals_observer;
   widget->AddRemovalsObserver(&removals_observer);
 
   View* parent = new View();
   widget->client_view()->AddChildView(parent);
@@ skipping 234 matching lines @@
     Transparency_DesktopWidgetTranslucent
 #endif
 TEST_F(CompositingWidgetTest, MAYBE_Transparency_DesktopWidgetTranslucent) {
   CheckAllWidgetsForOpacity(Widget::InitParams::TRANSLUCENT_WINDOW);
 }
 
 #endif  // !defined(OS_CHROMEOS)
 
 }  // namespace test
 }  // namespace views