[CrOS Tether] Add HasConnectedToHost property for Tether networks.

chromeos/network/network_state.cc

Index: chromeos/network/network_state.cc
diff --git a/chromeos/network/network_state.cc b/chromeos/network/network_state.cc
index 838faa0b3b8f1dfc9b6f01f6b71c7dc904403343..55775188273c64302a5c7be17255a5747ea5ce2e 100644
--- a/chromeos/network/network_state.cc
+++ b/chromeos/network/network_state.cc
@@ -267,6 +267,8 @@ void NetworkState::GetStateProperties(base::DictionaryValue* dictionary) const {
     dictionary->SetIntegerWithoutPathExpansion(kTetherBatteryPercentage,
                                                battery_percentage());
     dictionary->SetStringWithoutPathExpansion(kTetherCarrier, carrier());
+    dictionary->SetBooleanWithoutPathExpansion(kTetherHasConnectedToHost,
+                                               tether_has_connected_to_host());
     dictionary->SetIntegerWithoutPathExpansion(kTetherSignalStrength,
                                                signal_strength());
   }