This is the first pass at making GetIPConfigs asynchronous.

chromeos/dbus/shill_client_helper.h

Index: chromeos/dbus/shill_client_helper.h
diff --git a/chromeos/dbus/shill_client_helper.h b/chromeos/dbus/shill_client_helper.h
index 8782d90be40482cd4df5661092232ccee25ae6e4..cc3b0a3e17845c367b56d950d6a0f28ee83251e1 100644
--- a/chromeos/dbus/shill_client_helper.h
+++ b/chromeos/dbus/shill_client_helper.h
@@ -41,17 +41,18 @@ namespace chromeos {
 class ShillClientHelper {
  public:
   // A callback to handle PropertyChanged signals.
-  typedef base::Callback<void(const std::string& name,
-                              const base::Value& value)> PropertyChangedHandler;
+  typedef base::Callback<void(
+      const std::string& name,
+      scoped_ptr<base::Value> value)> PropertyChangedHandler;
 
   // A callback to handle responses for methods with DictionaryValue results.
   typedef base::Callback<void(
       DBusMethodCallStatus call_status,
-      const base::DictionaryValue& result)> DictionaryValueCallback;
+      scoped_ptr<base::DictionaryValue> result)> DictionaryValueCallback;
 
   // A callback to handle responses for methods with DictionaryValue results.
   // This is used by CallDictionaryValueMethodWithErrorCallback.
-  typedef base::Callback<void(const base::DictionaryValue& result
+  typedef base::Callback<void(scoped_ptr<base::DictionaryValue> result
                               )> DictionaryValueCallbackWithoutStatus;
 
   // A callback to handle errors for method call.