Use display_email() for Uber Tray messages.

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 618c56b3c16240ffded2835d4afdef1b07a48380..a5310ab4b865d0ce60256f873b11240596e54c7f 100644
--- a/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
+++ b/chrome/browser/chromeos/system/ash_system_tray_delegate.cc
@@ -241,7 +241,7 @@ class SystemTrayDelegate : public ash::SystemTrayDelegate,
   }
 
   virtual const std::string GetUserEmail() const OVERRIDE {
-    return UserManager::Get()->GetLoggedInUser().email();
+    return UserManager::Get()->GetLoggedInUser().display_email();
   }
 
   virtual const SkBitmap& GetUserImage() const OVERRIDE {