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

net/proxy/proxy_service.h

Index: net/proxy/proxy_service.h
diff --git a/net/proxy/proxy_service.h b/net/proxy/proxy_service.h
index 131c98c1a479d9fe928c0a4216cb3e1bc1cf307f..f9424d74128774726a2413ba784e9f6ad40c7999 100644
--- a/net/proxy/proxy_service.h
+++ b/net/proxy/proxy_service.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.
 
@@ -21,7 +21,6 @@
 
 class GURL;
 class MessageLoop;
-class URLRequestContext;
 
 namespace net {
 
@@ -29,6 +28,7 @@ class HostResolver;
 class InitProxyResolver;
 class ProxyResolver;
 class ProxyScriptFetcher;
+class URLRequestContext;
 
 // This class can be used to resolve the proxy server to use when loading a
 // HTTP(S) URL.  It uses the given ProxyResolver to handle the actual proxy