shill: Delete existing routes when the device is started.

BUG=chromium-os:27358
TEST=Unit tests, network_WiFiManager, manually add foreign routes and
ensure they are deleted, also test to make sure default route remains
after DHCP renewal

Change-Id: Ic26b70d685491f31699ff4684ed289e76af8a9ca
Reviewed-on: https://gerrit.chromium.org/gerrit/17640
Commit-Ready: Thieu Le <thieule@chromium.org>
Reviewed-by: Thieu Le <thieule@chromium.org>
Tested-by: Thieu Le <thieule@chromium.org>
diff --git a/mock_proxy_factory.h b/mock_proxy_factory.h
new file mode 100644
index 0000000..1d77e1c
--- /dev/null
+++ b/mock_proxy_factory.h
@@ -0,0 +1,24 @@
+// Copyright (c) 2012 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.
+
+#ifndef SHILL_MOCK_PROXY_FACTORY_
+#define SHILL_MOCK_PROXY_FACTORY_
+
+#include <gmock/gmock.h>
+
+#include "proxy_factory.h"
+
+namespace shill {
+
+class MockProxyFactory : public ProxyFactory {
+ public:
+  MockProxyFactory();
+  virtual ~MockProxyFactory();
+
+  MOCK_METHOD0(Init, void());
+};
+
+} // namespace shill
+
+#endif  // SHILL_MOCK_PROXY_FACTORY_