Remove fake client creation from DBusClients' Create() functions.

chromeos/dbus/shill_ipconfig_client_unittest.cc

Index: chromeos/dbus/shill_ipconfig_client_unittest.cc
diff --git a/chromeos/dbus/shill_ipconfig_client_unittest.cc b/chromeos/dbus/shill_ipconfig_client_unittest.cc
index e55231b053612b42e691432cc8cf73fd8c6c97c4..603ca2608698f43138888918958e712451b2cae0 100644
--- a/chromeos/dbus/shill_ipconfig_client_unittest.cc
+++ b/chromeos/dbus/shill_ipconfig_client_unittest.cc
@@ -33,7 +33,7 @@ class ShillIPConfigClientTest : public ShillClientUnittestBase {
   virtual void SetUp() {
     ShillClientUnittestBase::SetUp();
     // Create a client with the mock bus.
-    client_.reset(ShillIPConfigClient::Create(REAL_DBUS_CLIENT_IMPLEMENTATION));
+    client_.reset(ShillIPConfigClient::Create());
     client_->Init(mock_bus_.get());
     // Run the message loop to run the signal connection result callback.
     message_loop_.RunUntilIdle();