Data promo notification should follow the normal ash notifications theme. This

chrome/browser/chromeos/system/ash_system_tray_delegate.cc

Index: chrome/browser/chromeos/system/ash_system_tray_delegate.cc
diff --git a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
index 0f089e25c96cd16ca8722e8900ec9945164ec3e5..286ccdd98f1463ebcd8ce4b462c0148b4f728b05 100644
--- a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
+++ b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
@@ -158,7 +158,7 @@ class SystemTrayDelegate : public ash::SystemTrayDelegate,
                            public system::TimezoneSettings::Observer,
                            public BluetoothAdapter::Observer,
                            public SystemKeyEventListener::CapsLockObserver,
-                           public MessageBubbleLinkListener {
+                           public ash::NetworkTrayDelegate {
  public:
   explicit SystemTrayDelegate(ash::SystemTray* tray)
       : tray_(tray),
@@ -1202,8 +1202,8 @@ class SystemTrayDelegate : public ash::SystemTrayDelegate,
       observer->OnCapsLockChanged(enabled, search_mapped_to_caps_lock);
   }
 
-  // Overridden from MessageBubbleLinkListener
-  virtual void OnLinkActivated(size_t index) OVERRIDE {
+  // Overridden from ash::NetworkTrayDelegate
+  virtual void NotificationLinkClicked(size_t index) OVERRIDE {
     // If we have deal info URL defined that means that there're
     // 2 links in bubble. Let the user close it manually then thus giving
     // ability to navigate to second link.