net: Add namespace net to the remaining files under url_request directory.

net/proxy/proxy_script_fetcher.h

Index: net/proxy/proxy_script_fetcher.h
diff --git a/net/proxy/proxy_script_fetcher.h b/net/proxy/proxy_script_fetcher.h
index bf33bcb5179700a1ecd9daf69fb2d3f3b5f82a13..9829316e62636abe62ca74ed2f2ae8d07050b160 100644
--- a/net/proxy/proxy_script_fetcher.h
+++ b/net/proxy/proxy_script_fetcher.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -14,10 +14,11 @@
 #include "net/base/completion_callback.h"
 
 class GURL;
-class URLRequestContext;
 
 namespace net {
 
+class URLRequestContext;
+
 // Interface for downloading a PAC script. Implementations can enforce
 // timeouts, maximum size constraints, content encoding, etc..
 class ProxyScriptFetcher {