Implement new volume mute button.

ash/system/tray/tray_views.h

Index: ash/system/tray/tray_views.h
diff --git a/ash/system/tray/tray_views.h b/ash/system/tray/tray_views.h
index e1e612d0614a2ba0b7f8564f2c7ae29391ff0bb8..e78f29aa8ee43a2e89a321f4acffc27aa26a2bd1 100644
--- a/ash/system/tray/tray_views.h
+++ b/ash/system/tray/tray_views.h
@@ -8,6 +8,7 @@
 #include "ash/ash_export.h"
 #include "ui/gfx/font.h"
 #include "ui/gfx/size.h"
+#include "ui/views/controls/button/custom_button.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/button/text_button.h"
 #include "ui/views/controls/image_view.h"
@@ -227,6 +228,33 @@ class TrayPopupHeaderButton : public views::ToggleImageButton {
   DISALLOW_COPY_AND_ASSIGN(TrayPopupHeaderButton);
 };
 
+// A button with a bar image and title text below the bar image. These buttons
+// will be used in audio and brightness control UI, which can be toggled with
+// on/off states.
+class TrayBarButtonWithTitle : public views::CustomButton {
+ public:
+  TrayBarButtonWithTitle(views::ButtonListener* listener,
+                                  int title_id,
+                                  int width);
+  virtual ~TrayBarButtonWithTitle();
+
+  // Overridden from views::View:
+  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual void Layout() OVERRIDE;
+
+  void UpdateButton(bool control_on);
+
+ private:
+  class TrayBarButton;
+
+  TrayBarButton* image_;
+  views::Label* title_;
+  int width_;
+  int image_height_;
+
+  DISALLOW_COPY_AND_ASSIGN(TrayBarButtonWithTitle);
+};
+
 // The 'special' looking row in the uber-tray popups. This is usually the bottom
 // row in the popups, and has a fixed height.
 class SpecialPopupRow : public views::View {