Add an accessible name to the restart button

ash/system/tray_update.cc

Index: ash/system/tray_update.cc
diff --git a/ash/system/tray_update.cc b/ash/system/tray_update.cc
index 8feb0f643aa21822dbb284b3e2757c2d6634c617..e23f8c2195bbd6ef8233e2e085ab47ecdebefc63 100644
--- a/ash/system/tray_update.cc
+++ b/ash/system/tray_update.cc
@@ -36,6 +36,7 @@ class UpdateView : public ash::internal::ActionableView {
     AddChildView(image);
     AddChildView(new views::Label(
         bundle.GetLocalizedString(IDS_ASH_STATUS_TRAY_UPDATE)));
+    SetAccessibleName(bundle.GetLocalizedString(IDS_ASH_STATUS_TRAY_UPDATE));
   }
 
   virtual ~UpdateView() {}