Show number of hidden items in new-style list notification.

ui/message_center/message_center_style.h

 // 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.
 
 #ifndef UI_MESSAGE_CENTER_MESSAGE_CENTER_STYLE_H_
 #define UI_MESSAGE_CENTER_MESSAGE_CENTER_STYLE_H_
 
 #include <stddef.h>
 
 #include "build/build_config.h"
@@ skipping 90 matching lines @@
     SkColorSetA(SK_ColorWHITE, 0.9 * 0xff);
 
 // Limits.
 
 // Given the size of an image, returns the size of the properly scaled-up image
 // which fits into |container_size|.
 MESSAGE_CENTER_EXPORT gfx::Size GetImageSizeForContainerSize(
     const gfx::Size& container_size,
     const gfx::Size& image_size);
 
-const size_t kNotificationMaximumItems = 5;     // For list notifications.
+// For list notifications.
+// Not used when --enabled-new-style-notification is set.
+const size_t kNotificationMaximumItems = 5;
 
 // Timing.
 const int kAutocloseDefaultDelaySeconds = 8;
 const int kAutocloseHighPriorityDelaySeconds = 25;
 // Web notifications use a larger timeout for now, which improves re-engagement.
 // TODO(johnme): Use Finch to experiment with different values, then consider
 // replacing kAutocloseDefaultDelaySeconds with this (https://crbug.com/530697)
 const int kAutocloseWebPageDelaySeconds = 20;
 
 // Buttons.
@@ skipping 43 matching lines @@
 
 const SkColor kMessageCenterBackgroundColor = SkColorSetRGB(0xee, 0xee, 0xee);
 // Separator color for the tray.
 const SkColor kFooterDelimiterColor = SkColorSetRGB(0xcc, 0xcc, 0xcc);
 // Text color for tray labels.
 const SkColor kFooterTextColor = SkColorSetRGB(0x7b, 0x7b, 0x7b);
 
 }  // namespace message_center
 
 #endif  // UI_MESSAGE_CENTER_MESSAGE_CENTER_STYLE_H_