Add Ash notification UI for OutOfCredits network property

chromeos/network/network_state.h

Index: chromeos/network/network_state.h
diff --git a/chromeos/network/network_state.h b/chromeos/network/network_state.h
index f8f9567f2c11737f7eeb3ef0b524b4bbe4d44252..6e7890b93bad5dff04b1d6549cdce8de24839a3f 100644
--- a/chromeos/network/network_state.h
+++ b/chromeos/network/network_state.h
@@ -49,6 +49,7 @@ class CHROMEOS_EXPORT NetworkState : public ManagedState {
   bool activate_over_non_cellular_networks() const {
     return activate_over_non_cellular_networks_;
   }
+  bool cellular_out_of_credits() const { return cellular_out_of_credits_; }
 
   bool IsConnectedState() const;
   bool IsConnectingState() const;
@@ -80,6 +81,7 @@ class CHROMEOS_EXPORT NetworkState : public ManagedState {
   std::string activation_state_;
   std::string roaming_;
   bool activate_over_non_cellular_networks_;
+  bool cellular_out_of_credits_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkState);
 };