Fix memory leak in NotificationControlButtonsView

ui/message_center/views/notification_control_buttons_view.cc

 // Copyright 2017 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/message_center/views/notification_control_buttons_view.h"
 
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/events/event.h"
 #include "ui/gfx/animation/linear_animation.h"
@@ skipping 28 matching lines @@
       bgcolor_target_(kInitialBackgroundColor) {
   DCHECK(message_view);
   SetLayoutManager(new views::BoxLayout(views::BoxLayout::kHorizontal));
   SetBackground(views::CreateSolidBackground(kInitialBackgroundColor));
 }
 
 NotificationControlButtonsView::~NotificationControlButtonsView() = default;
 
 void NotificationControlButtonsView::ShowCloseButton(bool show) {
   if (show && !close_button_) {
-    close_button_ = new message_center::PaddedButton(this);
+    close_button_ = base::MakeUnique<message_center::PaddedButton>(this);
+    close_button_->set_owned_by_client();
     close_button_->SetImage(views::CustomButton::STATE_NORMAL,
                             message_center::GetCloseIcon());
     close_button_->SetAccessibleName(l10n_util::GetStringUTF16(
         IDS_MESSAGE_CENTER_CLOSE_NOTIFICATION_BUTTON_ACCESSIBLE_NAME));
     close_button_->SetTooltipText(l10n_util::GetStringUTF16(
         IDS_MESSAGE_CENTER_CLOSE_NOTIFICATION_BUTTON_TOOLTIP));
     close_button_->SetBackground(
         views::CreateSolidBackground(SK_ColorTRANSPARENT));
 
     // Add the button at the last.
     DCHECK_LE(child_count(), 1);
-    AddChildView(close_button_);
+    AddChildView(close_button_.get());
   } else if (!show && close_button_) {
-    RemoveChildView(close_button_);
-    close_button_ = nullptr;
+    DCHECK(Contains(close_button_.get()));
+    close_button_.reset();
   }
 }
 
 void NotificationControlButtonsView::ShowSettingsButton(bool show) {
   if (show && !settings_button_) {
-    settings_button_ = new message_center::PaddedButton(this);
+    settings_button_ = base::MakeUnique<message_center::PaddedButton>(this);
+    settings_button_->set_owned_by_client();
     settings_button_->SetImage(views::CustomButton::STATE_NORMAL,
                                message_center::GetSettingsIcon());
     settings_button_->SetAccessibleName(l10n_util::GetStringUTF16(
         IDS_MESSAGE_NOTIFICATION_SETTINGS_BUTTON_ACCESSIBLE_NAME));
     settings_button_->SetTooltipText(l10n_util::GetStringUTF16(
         IDS_MESSAGE_NOTIFICATION_SETTINGS_BUTTON_ACCESSIBLE_NAME));
     settings_button_->SetBackground(
         views::CreateSolidBackground(SK_ColorTRANSPARENT));
 
     // Add the button at the first.
     DCHECK_LE(child_count(), 1);
-    AddChildViewAt(settings_button_, 0);
+    AddChildViewAt(settings_button_.get(), 0);
   } else if (!show && settings_button_) {
-    RemoveChildView(settings_button_);
-    settings_button_ = nullptr;
+    DCHECK(Contains(settings_button_.get()));
+    settings_button_.reset();
   }
 }
 
 void NotificationControlButtonsView::SetBackgroundColor(
     const SkColor& target_bgcolor) {
   if (background()->get_color() != target_bgcolor) {
     bgcolor_origin_ = background()->get_color();
     bgcolor_target_ = target_bgcolor;
 
     if (bgcolor_animation_)
@@ skipping 10 matching lines @@
 }
 
 bool NotificationControlButtonsView::IsCloseButtonFocused() const {
   return close_button_ && close_button_->HasFocus();
 }
 
 bool NotificationControlButtonsView::IsSettingsButtonFocused() const {
   return settings_button_ && settings_button_->HasFocus();
 }
 
+message_center::PaddedButton*
+NotificationControlButtonsView::close_button_for_testing() const {
+  return close_button_.get();
+}
+
+message_center::PaddedButton*
+NotificationControlButtonsView::settings_button_for_testing() const {
+  return settings_button_.get();
+}
+
 const char* NotificationControlButtonsView::GetClassName() const {
   return kViewClassName;
 }
 
 void NotificationControlButtonsView::ButtonPressed(views::Button* sender,
                                                    const ui::Event& event) {
-  if (close_button_ && sender == close_button_) {
+  if (close_button_ && sender == close_button_.get()) {
     message_view_->OnCloseButtonPressed();
-  } else if (settings_button_ && sender == settings_button_) {
+  } else if (settings_button_ && sender == settings_button_.get()) {
     message_view_->OnSettingsButtonPressed();
   }
 }
 
 void NotificationControlButtonsView::AnimationProgressed(
     const gfx::Animation* animation) {
   DCHECK_EQ(animation, bgcolor_animation_.get());
 
   const SkColor color = gfx::Tween::ColorValueBetween(
       animation->GetCurrentValue(), bgcolor_origin_, bgcolor_target_);
@@ skipping 12 matching lines @@
     const gfx::Animation* animation) {
   // The animation is never cancelled explicitly.
   NOTREACHED();
 
   bgcolor_origin_ = bgcolor_target_;
   SetBackground(views::CreateSolidBackground(bgcolor_target_));
   SchedulePaint();
 }
 
 }  // namespace message_center