Follow-up fixes to http://crrev.com/12638033.

ui/message_center/views/message_center_bubble.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 "ui/message_center/views/message_center_bubble.h"
 
 #include <map>
 
 #include "grit/ui_strings.h"
 #include "third_party/skia/include/core/SkPaint.h"
@@ skipping 271 matching lines @@
  private:
   int min_height_;
   int max_height_;
 
   DISALLOW_COPY_AND_ASSIGN(BoundedScrollView);
 };
 
 // Displays a list of messages.
 class MessageListView : public views::View {
  public:
-  MessageListView() {
+  MessageListView(views::View* container) : container_(container) {
     if (IsRichNotificationEnabled()) {
       // Set the margin to 0 for the layout. BoxLayout assumes the same margin
       // for top and bottom, but the bottom margin here should be smaller
       // because of the shadow of message view. Use an empty border instead
       // to provide this margin.
       gfx::Insets shadow_insets = MessageView::GetShadowInsets();
       SetLayoutManager(
           new views::BoxLayout(views::BoxLayout::kVertical,
                                0,
                                0,
                                kMarginBetweenItems - shadow_insets.bottom()));
       set_background(views::Background::CreateSolidBackground(
           kMessageCenterBackgroundColor));
       set_border(views::Border::CreateEmptyBorder(
           kMarginBetweenItems - shadow_insets.top(), /* top */
           kMarginBetweenItems - shadow_insets.left(), /* left */
           0,  /* bottom */
           kMarginBetweenItems - shadow_insets.right() /* right */ ));
     } else {
       views::BoxLayout* layout =
           new views::BoxLayout(views::BoxLayout::kVertical, 0, 0, 1);
       layout->set_spread_blank_space(true);
       SetLayoutManager(layout);
     }
   }
 
   virtual ~MessageListView() {
   }
 
+ protected:
+  // Overridden from views::View:
+  void ChildPreferredSizeChanged(View* child) {
+    container_->Layout();
+  }

[dharcourt, 2013/03/13 22:47:51]

Without this the MessageCenterView never would get notified of the preferred
size change that accompanies a notification expansion, so it wouldn't have a
chance to update the message center. This fixes that.

+
  private:
+  views::View* container_;  // Weak reference.
+
   DISALLOW_COPY_AND_ASSIGN(MessageListView);
 };
 
 }  // namespace
 
 // View that displays the whole message center.
 class MessageCenterView : public views::View {
  public:
   MessageCenterView(MessageCenterBubble* bubble,
                     NotificationChangeObserver* observer)
@@ skipping 13 matching lines @@
     const int min_height = kMessageBubbleBaseMinHeight - button_height;
     const int max_height = bubble_->max_height() - button_height;
     scroller_ = new BoundedScrollView(min_height, max_height);
 
     if (get_use_acceleration_when_possible()) {
       scroller_->SetPaintToLayer(true);
       scroller_->SetFillsBoundsOpaquely(false);
       scroller_->layer()->SetMasksToBounds(true);
     }
 
-    message_list_view_ = new MessageListView();
+    message_list_view_ = new MessageListView(this);
     scroller_->SetContents(message_list_view_);
 
     AddChildView(scroller_);
     AddChildView(button_view_);
   }
 
   void FocusContents() {
   }
 
   void UpdateAllNotifications(
@@ skipping 118 matching lines @@
 }
 
 void MessageCenterBubble::OnMouseExitedView() {
 }
 
 size_t MessageCenterBubble::NumMessageViewsForTest() const {
   return contents_view_->NumMessageViews();
 }
 
 }  // namespace message_center