shill: Enable the ModemManager.Modem on Cellular device start.

Also, move DBus.Object/Connection properties to the Cellular device,
initializing them to the right values.

BUG=chromium-os:18315
TEST=unit tests, tested on device

Change-Id: I5788ca7aa375afee757fbd96edf96f9d07f29ded
Reviewed-on: http://gerrit.chromium.org/gerrit/4947
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/modem_proxy.cc b/modem_proxy.cc
new file mode 100644
index 0000000..9bcf219
--- /dev/null
+++ b/modem_proxy.cc
@@ -0,0 +1,37 @@
+// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "shill/modem_proxy.h"
+
+#include <base/logging.h>
+
+using std::string;
+
+namespace shill {
+
+ModemProxy::ModemProxy(DBus::Connection *connection,
+                       const string &path,
+                       const string &service)
+    : proxy_(connection, path, service) {}
+
+ModemProxy::~ModemProxy() {}
+
+void ModemProxy::Enable(const bool enable) {
+  proxy_.Enable(enable);
+}
+
+ModemProxy::Proxy::Proxy(DBus::Connection *connection,
+                         const string &path,
+                         const string &service)
+    : DBus::ObjectProxy(*connection, path, service.c_str()) {}
+
+ModemProxy::Proxy::~Proxy() {}
+
+void ModemProxy::Proxy::StateChanged(const uint32 &old_state,
+                                     const uint32 &new_state,
+                                     const uint32 &reason) {
+  VLOG(2) << __func__;
+}
+
+}  // namespace shill