views: introduce unique_ptr variants of Widget::CreateWindowWith

These methods express that the caller is passing in ownership of the
delegate, and assert that the delegate believes it is owned by the
widget.

This change also corrects a flaw in ownership handling in an ash
unittest: some of the created delegates were passed around as raw
pointers, and one was sort of leaked (not actually leaked, but
destroyed in an extremely non-obvious way).

Bug: 1075649
Change-Id: I655dfe3e2466032b85247341f43b1b2d75c0b561
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2446015Reviewed-by: Peter Boström <pbos@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813416}

ash/shell_unittest.cc

@@ -134,12 +134,13 @@ void ExpectAllContainers() {
   EXPECT_FALSE(Shell::GetContainer(root_window, kShellWindowId_PhantomWindow));
 }
 
-views::WidgetDelegateView* CreateModalWidgetDelegate() {
+std::unique_ptr<views::WidgetDelegateView> CreateModalWidgetDelegate() {
   auto delegate = std::make_unique<views::WidgetDelegateView>();
   delegate->SetCanResize(true);
   delegate->SetModalType(ui::MODAL_TYPE_SYSTEM);
+  delegate->SetOwnedByWidget(true);
   delegate->SetTitle(base::ASCIIToUTF16("Modal Window"));
-  return delegate.release();
+  return delegate;
 }
 
 class SimpleMenuDelegate : public ui::SimpleMenuModel::Delegate {
@@ -322,14 +323,6 @@ TEST_F(ShellTest, CreateModalWindow) {
   widget->Close();
 }
 
-class TestModalDialogDelegate : public views::DialogDelegateView {
- public:
-  TestModalDialogDelegate() = default;
-
-  // Overridden from views::WidgetDelegate:
-  ui::ModalType GetModalType() const override { return ui::MODAL_TYPE_SYSTEM; }
-};
-
 TEST_F(ShellTest, CreateLockScreenModalWindow) {
   views::Widget::InitParams widget_params(
       views::Widget::InitParams::TYPE_WINDOW);
@@ -383,9 +376,9 @@ TEST_F(ShellTest, CreateLockScreenModalWindow) {
       Shell::GetPrimaryRootWindow(), kShellWindowId_SystemModalContainer);
   EXPECT_EQ(modal_container, modal_widget->GetNativeWindow()->parent());
 
-  // Modal dialog without parent, caused crash see crbug.com/226141
+  // Modal widget without parent, caused crash see crbug.com/226141
   views::Widget* modal_dialog = views::DialogDelegate::CreateDialogWidget(
-      new TestModalDialogDelegate(), GetContext(), nullptr);
+      CreateModalWidgetDelegate(), GetContext(), nullptr);
 
   modal_dialog->Show();
   EXPECT_FALSE(modal_dialog->GetNativeView()->HasFocus());

ui/views/widget/widget.cc

@@ -197,6 +197,13 @@ Widget* Widget::CreateWindowWithParent(WidgetDelegate* delegate,
   return new Widget(std::move(params));
 }
 
+Widget* Widget::CreateWindowWithParent(std::unique_ptr<WidgetDelegate> delegate,
+                                       gfx::NativeView parent,
+                                       const gfx::Rect& bounds) {
+  DCHECK(delegate->owned_by_widget());
+  return CreateWindowWithParent(delegate.release(), parent, bounds);
+}
+
 // static
 Widget* Widget::CreateWindowWithContext(WidgetDelegate* delegate,
                                         gfx::NativeWindow context,
@@ -208,6 +215,15 @@ Widget* Widget::CreateWindowWithContext(WidgetDelegate* delegate,
   return new Widget(std::move(params));
 }
 
+// static
+Widget* Widget::CreateWindowWithContext(
+    std::unique_ptr<WidgetDelegate> delegate,
+    gfx::NativeWindow context,
+    const gfx::Rect& bounds) {
+  DCHECK(delegate->owned_by_widget());
+  return CreateWindowWithContext(delegate.release(), context, bounds);
+}
+
 // static
 Widget* Widget::GetWidgetForNativeView(gfx::NativeView native_view) {
   internal::NativeWidgetPrivate* native_widget =

ui/views/widget/widget.h

@@ -396,16 +396,26 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
   // Creates a decorated window Widget with the specified properties. The
   // returned Widget is owned by its NativeWidget; see Widget class comment for
   // details.
+  // The std::unique_ptr variant requires that delegate->owned_by_widget().
   static Widget* CreateWindowWithParent(WidgetDelegate* delegate,
                                         gfx::NativeView parent,
                                         const gfx::Rect& bounds = gfx::Rect());
+  static Widget* CreateWindowWithParent(
+      std::unique_ptr<WidgetDelegate> delegate,
+      gfx::NativeView parent,
+      const gfx::Rect& bounds = gfx::Rect());
 
   // Creates a decorated window Widget in the same desktop context as |context|.
   // The returned Widget is owned by its NativeWidget; see Widget class comment
   // for details.
+  // The std::unique_ptr variant requires that delegate->owned_by_widget().
   static Widget* CreateWindowWithContext(WidgetDelegate* delegate,
                                          gfx::NativeWindow context,
                                          const gfx::Rect& bounds = gfx::Rect());
+  static Widget* CreateWindowWithContext(
+      std::unique_ptr<WidgetDelegate> delegate,
+      gfx::NativeWindow context,
+      const gfx::Rect& bounds = gfx::Rect());
 
   // Closes all Widgets that aren't identified as "secondary widgets". Called
   // during application shutdown when the last non-secondary widget is closed.