views: Make view::Views::GetPreferredSize() const.

ash/system/web_notification/web_notification_tray.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 "ash/system/web_notification/web_notification_tray.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_layout_manager_observer.h"
@@ skipping 249 matching lines @@
     // TODO(mukai): move NINE_PLUS message to ui_strings, it doesn't need to be
     // in ash_strings.
     unread_label_->SetText((unread_count > 9) ?
         l10n_util::GetStringUTF16(IDS_ASH_NOTIFICATION_UNREAD_COUNT_NINE_PLUS) :
         base::FormatNumber(unread_count));
     UpdateIconVisibility();
   }
 
  protected:
   // Overridden from views::ImageButton:
-  virtual gfx::Size GetPreferredSize() OVERRIDE {
+  virtual gfx::Size GetPreferredSize() const OVERRIDE {
     return gfx::Size(kShelfItemHeight, kShelfItemHeight);
   }
 
   virtual int GetHeightForWidth(int width) OVERRIDE {
     return GetPreferredSize().height();
   }
 
  private:
   void UpdateIconVisibility() {
     unread_label_->SetEnabledColor(
@@ skipping 330 matching lines @@
 
 message_center::MessageCenterBubble*
 WebNotificationTray::GetMessageCenterBubbleForTest() {
   if (!message_center_bubble())
     return NULL;
   return static_cast<message_center::MessageCenterBubble*>(
       message_center_bubble()->bubble());
 }
 
 }  // namespace ash