Add IPv6 Address to status tray

chromeos/network/device_state.h

Index: chromeos/network/device_state.h
diff --git a/chromeos/network/device_state.h b/chromeos/network/device_state.h
index 6542ff78d2ea370d31f89cde5a591b6f1dca91b5..00e49078d4207c13931887629ad7b7391625ab9c 100644
--- a/chromeos/network/device_state.h
+++ b/chromeos/network/device_state.h
@@ -60,6 +60,9 @@ class CHROMEOS_EXPORT DeviceState : public ManagedState {
     return eap_authentication_completed_;
   }
 
+  // Returns the IP Address for |type| if it exists or an empty string.
+  std::string GetIpAddressByType(const std::string& type) const;
+
   // Returns true if the technology family is GSM and sim_present_ is false.
   bool IsSimAbsent() const;