This is the first pass at making GetIPConfigs asynchronous.

chromeos/dbus/shill_service_client.cc

Index: chromeos/dbus/shill_service_client.cc
diff --git a/chromeos/dbus/shill_service_client.cc b/chromeos/dbus/shill_service_client.cc
index f208966ab3b6b690177fa801e720597a898cb630..cea7b78960f98675e55a431768df02de3ba843bb 100644
--- a/chromeos/dbus/shill_service_client.cc
+++ b/chromeos/dbus/shill_service_client.cc
@@ -36,8 +36,8 @@ void OnGetPropertiesError(
   else
     LOG(ERROR) << log_string;
 
-  base::DictionaryValue empty_dictionary;
-  callback.Run(DBUS_METHOD_CALL_FAILURE, empty_dictionary);
+  scoped_ptr<base::DictionaryValue> empty_dictionary(new base::DictionaryValue);
+  callback.Run(DBUS_METHOD_CALL_FAILURE, empty_dictionary.Pass());
 }
 
 // The ShillServiceClient implementation.
@@ -356,11 +356,12 @@ class ShillServiceClientStubImpl : public ShillServiceClient,
     base::DictionaryValue* dict = NULL;
     if (!stub_services_.GetDictionaryWithoutPathExpansion(
             service_path.value(), &dict)) {
-      base::DictionaryValue empty_dictionary;
-      callback.Run(DBUS_METHOD_CALL_FAILURE, empty_dictionary);
+      scoped_ptr<base::DictionaryValue> empty(new base::DictionaryValue);
+      callback.Run(DBUS_METHOD_CALL_FAILURE, empty.Pass());
       return;
     }
-    callback.Run(DBUS_METHOD_CALL_SUCCESS, *dict);
+    scoped_ptr<base::DictionaryValue> result_copy(dict->DeepCopy());
+    callback.Run(DBUS_METHOD_CALL_SUCCESS, result_copy.Pass());
   }
 
   void NotifyObserversPropertyChanged(const dbus::ObjectPath& service_path,