Introduce NetworkState::is_captive_portal()

chromeos/network/onc/onc_translator_shill_to_onc.cc

Index: chromeos/network/onc/onc_translator_shill_to_onc.cc
diff --git a/chromeos/network/onc/onc_translator_shill_to_onc.cc b/chromeos/network/onc/onc_translator_shill_to_onc.cc
index f49742179ed6f3733c28194914e3e9d3f9e11e45..3de5f77ac946fca45e9509f3892bf8001f494986 100644
--- a/chromeos/network/onc/onc_translator_shill_to_onc.cc
+++ b/chromeos/network/onc/onc_translator_shill_to_onc.cc
@@ -434,8 +434,8 @@ void ShillToONCTranslator::TranslateNetworkWithState() {
     }
     onc_object_->SetStringWithoutPathExpansion(
         ::onc::network_config::kConnectionState, onc_state);
-    // Only set 'RestrictedConnectivity' if true.
-    if (state == shill::kStatePortal) {
+    // Only set 'RestrictedConnectivity' if captive portal state is true.
+    if (NetworkState::NetworkStateIsCaptivePortal(*shill_dictionary_)) {
       onc_object_->SetBooleanWithoutPathExpansion(
           ::onc::network_config::kRestrictedConnectivity, true);
     }