Use URLRequestContextBuilderMojo to create the SystemURLRequestContext.

chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.cc

Index: chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.cc
diff --git a/chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.cc b/chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.cc
new file mode 100644
index 0000000000000000000000000000000000000000..89b43126f6313bd63c5cfed3c59bb15b07626432
--- /dev/null
+++ b/chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.cc
@@ -0,0 +1,24 @@
+// Copyright 2017 The Chromium 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 "chromeos/network/dhcp_proxy_script_fetcher_factory_chromeos.h"
+
+#include "base/memory/ptr_util.h"
+#include "chromeos/network/dhcp_proxy_script_fetcher_chromeos.h"
+
+namespace chromeos {
+
+DhcpProxyScriptFetcherFactoryChromeos::DhcpProxyScriptFetcherFactoryChromeos() {
+}
+
+DhcpProxyScriptFetcherFactoryChromeos::
+    ~DhcpProxyScriptFetcherFactoryChromeos() {}
+
+std::unique_ptr<net::DhcpProxyScriptFetcher>
+DhcpProxyScriptFetcherFactoryChromeos::Create(
+    net::URLRequestContext* url_request_context) {
+  return base::MakeUnique<DhcpProxyScriptFetcherChromeos>(url_request_context);
+}
+
+}  // namespace chromeos