Remove the most obvious dead code from message center.

ui/message_center/views/message_center_view.h

Index: ui/message_center/views/message_center_view.h
diff --git a/ui/message_center/views/message_center_view.h b/ui/message_center/views/message_center_view.h
index 593c24f462685792ab9013c0792ab0f26341c4e0..6ead0abf7a6f4b22b6521bc1bf938a96d5962d24 100644
--- a/ui/message_center/views/message_center_view.h
+++ b/ui/message_center/views/message_center_view.h
@@ -11,6 +11,7 @@
 #include "ui/message_center/message_center_export.h"
 #include "ui/message_center/message_center_observer.h"
 #include "ui/message_center/notification_list.h"
+#include "ui/views/controls/button/button.h"
 
 namespace ui {
 class MultiAnimation;
@@ -24,6 +25,7 @@ namespace message_center {
 
 class MessageCenter;
 class MessageCenterBubble;
+class NotificationCenterButton;
 class MessageCenterTray;
 class MessageCenterView;
 class MessageView;
@@ -34,17 +36,24 @@ class NotifierSettingsView;
 
 // If you know how to better hide this implementation class please do so, and
 // otherwise please refrain from using it :-).
-class MessageCenterButtonBar : public views::View {
+class MessageCenterButtonBar : public views::View,
+                               public views::ButtonListener {
  public:
   MessageCenterButtonBar(MessageCenterView* message_center_view,
                          MessageCenter* message_center);
   virtual ~MessageCenterButtonBar();
 
   virtual void SetAllButtonsEnabled(bool enabled);
-
   void SetCloseAllVisible(bool visible);
 
- protected:
+ private:
+  // Overridden from views::View:
+  virtual void ChildVisibilityChanged(views::View* child) OVERRIDE;
+
+  // Overridden from views::ButtonListener:
+  virtual void ButtonPressed(views::Button* sender, const ui::Event& event)
+      OVERRIDE;
+
   MessageCenterView* message_center_view() const {
     return message_center_view_;
   }
@@ -55,11 +64,12 @@ class MessageCenterButtonBar : public views::View {
     close_all_button_ = button;
   }
 
- private:
   MessageCenterView* message_center_view_;  // Weak reference.
   MessageCenter* message_center_;  // Weak reference.
   MessageCenterTray* tray_;  // Weak reference.
   views::Button* close_all_button_;
+  NotificationCenterButton* settings_button_;
+  NotificationCenterButton* quiet_mode_button_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageCenterButtonBar);
 };