Add an opt-out header for HTTP throttling. Never throttle for localhost.

net/url_request/url_request_throttler_entry_interface.h

Index: net/url_request/url_request_throttler_entry_interface.h
diff --git a/net/url_request/url_request_throttler_entry_interface.h b/net/url_request/url_request_throttler_entry_interface.h
index 63dd14cbf0e250ac30377341d7d4ea810787a6cb..288b8275515a8a6013aa6acb93e96a85857eb650 100644
--- a/net/url_request/url_request_throttler_entry_interface.h
+++ b/net/url_request/url_request_throttler_entry_interface.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.
 
@@ -43,6 +43,7 @@ class URLRequestThrottlerEntryInterface
 
   // This method needs to be called each time a response is received.
   virtual void UpdateWithResponse(
+      const std::string& host,
       const URLRequestThrottlerHeaderInterface* response) = 0;
 
   // Lets higher-level modules, that know how to parse particular response