Revert of Suspect that this is causing crash, reverting.

ui/message_center/views/message_center_view.cc

 // Copyright (c) 2013 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/message_center_view.h"
 
 #include <list>
 #include <map>
 
 #include "base/command_line.h"
@@ skipping 36 matching lines @@
 namespace {
 
 const SkColor kNoNotificationsTextColor = SkColorSetRGB(0xb4, 0xb4, 0xb4);
 #if defined(OS_LINUX) && defined(OS_CHROMEOS)
 const SkColor kTransparentColor = SkColorSetARGB(0, 0, 0, 0);
 #endif
 const int kAnimateClearingNextNotificationDelayMS = 40;
 
 const int kDefaultAnimationDurationMs = 120;
 const int kDefaultFrameRateHz = 60;
+
+void SetViewHierarchyEnabled(views::View* view, bool enabled) {
+  for (int i = 0; i < view->child_count(); i++)
+    SetViewHierarchyEnabled(view->child_at(i), enabled);
+  view->SetEnabled(enabled);
+}
+
 }  // namespace
 
 class NoNotificationMessageView : public views::View {
  public:
   NoNotificationMessageView();
   ~NoNotificationMessageView() override;
 
   // Overridden from views::View.
   gfx::Size GetPreferredSize() const override;
   int GetHeightForWidth(int width) const override;
@@ skipping 611 matching lines @@
   settings_transition_animation_->set_continuous(false);
   settings_transition_animation_->Start();
 
   button_bar_->SetBackArrowVisible(visible);
 }
 
 void MessageCenterView::ClearAllNotifications() {
   if (is_closing_)
     return;
 
-  scroller_->SetEnabled(false);
+  SetViewHierarchyEnabled(scroller_, false);
   button_bar_->SetAllButtonsEnabled(false);
   message_list_view_->ClearAllNotifications(scroller_->GetVisibleRect());
 }
 
 void MessageCenterView::OnAllNotificationsCleared() {
-  scroller_->SetEnabled(true);
+  SetViewHierarchyEnabled(scroller_, true);
   button_bar_->SetAllButtonsEnabled(true);
   button_bar_->SetCloseAllButtonEnabled(false);
   message_center_->RemoveAllVisibleNotifications(true);  // Action by user.
 }
 
 size_t MessageCenterView::NumMessageViewsForTest() const {
   return message_list_view_->child_count();
 }
 
 void MessageCenterView::OnSettingsChanged() {
@@ skipping 151 matching lines @@
     // without re-focusing by tab key.
     if (view->IsCloseButtonFocused() ||
         view == GetFocusManager()->GetFocusedView()) {
       views::View* next_focused_view = NULL;
       if (message_list_view_->child_count() > index + 1)
         next_focused_view = message_list_view_->child_at(index + 1);
       else if (index > 0)
         next_focused_view = message_list_view_->child_at(index - 1);
 
       if (next_focused_view) {
-        if (view->IsCloseButtonFocused())
+        if (view->IsCloseButtonFocused()) {
           // Safe cast since all views in MessageListView are MessageViews.
           static_cast<MessageView*>(
               next_focused_view)->RequestFocusOnCloseButton();
-        else
+        } else {
           next_focused_view->RequestFocus();
+        }
       }
     }
   }
   message_list_view_->RemoveNotification(view);
   notification_views_.erase(view_iter);
   NotificationsChanged();
 }
 
 void MessageCenterView::OnNotificationUpdated(const std::string& id) {
   NotificationViewsMap::const_iterator view_iter = notification_views_.find(id);
@@ skipping 118 matching lines @@
   scroller_->InvalidateLayout();
   PreferredSizeChanged();
   Layout();
 }
 
 void MessageCenterView::SetNotificationViewForTest(MessageView* view) {
   message_list_view_->AddNotificationAt(view, 0);
 }
 
 }  // namespace message_center