Add battery status to settings row in uber tray bubble.

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 b07b1edf7180750fb78ba34471b32a49e968662a..8a2ba85d5babe4ebfd0de829dcb166e352320341 100644
--- a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
+++ b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
@@ -931,9 +931,8 @@ class SystemTrayDelegate : public ash::SystemTrayDelegate,
 
   virtual void PowerChanged(const PowerSupplyStatus& power_status) OVERRIDE {
     power_supply_status_ = power_status;
-    ash::PowerStatusObserver* observer = tray_->power_status_observer();
-    if (observer)
-      observer->OnPowerStatusChanged(power_status);
+    FOR_EACH_OBSERVER(ash::PowerStatusObserver, tray_->power_status_observers(),
+        OnPowerStatusChanged(power_status));
   }
 
   virtual void SystemResumed() OVERRIDE {