Adds support for the DHCP portion of the WPAD (proxy auto-discovery) protocol.

net/proxy/dhcp_proxy_script_fetcher_factory.cc

Index: net/proxy/dhcp_proxy_script_fetcher_factory.cc
diff --git a/net/proxy/dhcp_proxy_script_fetcher_factory.cc b/net/proxy/dhcp_proxy_script_fetcher_factory.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8af3f8a077909d9872aa921b53a44c59bc352feb
--- /dev/null
+++ b/net/proxy/dhcp_proxy_script_fetcher_factory.cc
@@ -0,0 +1,55 @@
+// Copyright (c) 2011 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 "net/proxy/dhcp_proxy_script_fetcher_factory.h"
+
+#include "net/base/net_errors.h"
+#include "net/proxy/dhcp_proxy_script_fetcher.h"
+
+#if defined(OS_WIN)
+#include "net/proxy/dhcp_proxy_script_fetcher_win.h"
+#endif
+
+namespace net {
+
+bool DhcpProxyScriptFetcherFactory::feature_enabled_ = false;
+
+// static
+DhcpProxyScriptFetcher* DhcpProxyScriptFetcherFactory::Create(
+    URLRequestContext* context) {
+  if (!feature_enabled_) {
+    return new DoNothingDhcpProxyScriptFetcher();
+  } else {
+    DCHECK(IsSupported());
+    DhcpProxyScriptFetcher* ret = NULL;
+#if defined(OS_WIN)
+    ret = new WindowsDhcpProxyScriptFetcher(context);
+#endif
+    DCHECK(ret);
+    return ret;
+  }
+}
+
+// static
+void DhcpProxyScriptFetcherFactory::SetEnabled(bool enabled) {
+  if (IsSupported()) {
+    feature_enabled_ = enabled;
+  }
+}
+
+// static
+bool DhcpProxyScriptFetcherFactory::IsEnabled() {
+  return feature_enabled_;
+}
+
+// static
+bool DhcpProxyScriptFetcherFactory::IsSupported() {
+#if defined(OS_WIN)
+  return true;
+#else
+  return false;
+#endif
+}
+
+}  // namespace net