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

net/url_request/https_prober.h

Index: net/url_request/https_prober.h
diff --git a/net/url_request/https_prober.h b/net/url_request/https_prober.h
index 5d1a6222dd4b5feb18740e26795a6c81dd2fa517..6540224d8e0a4e36bffb27098016af4369df849a 100644
--- a/net/url_request/https_prober.h
+++ b/net/url_request/https_prober.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/url_request/url_request.h"
 
 template <typename T> struct DefaultSingletonTraits;
-class URLRequestContext;
 
 namespace net {
 
+class URLRequestContext;
+
 // This should be scoped inside HTTPSProber, but VC cannot compile
 // HTTPProber::Delegate when HTTPSProber also inherits from
 // net::URLRequest::Delegate.
@@ -77,4 +78,5 @@ class HTTPSProber : public net::URLRequest::Delegate {
 };
 
 }  // namespace net
-#endif
+
+#endif  // NET_BASE_HTTPS_PROBER_H_