Implement exponential back-off mechanism and enforce it at the URLRequestHttpJob level.

net/url_request/request_throttler_header_adapter.h

+// Copyright (c) 2010 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.
+
+#ifndef NET_URL_REQUEST_REQUEST_THROTTLER_HEADER_ADAPTER_H_
+#define NET_URL_REQUEST_REQUEST_THROTTLER_HEADER_ADAPTER_H_
+
+#include <string>
+
+#include "base/scoped_ptr.h"

[willchan no longer on Chromium, 2010/11/24 10:14:50]

Don't you need ref_counted.h for scoped_refptr instead?

[yzshen, 2010/11/24 19:09:30]

Done.

+#include "net/http/http_response_headers.h"

[willchan no longer on Chromium, 2010/11/24 10:14:50]

Can net::HttpResponseHeaders be forward declared instead?

[yzshen, 2010/11/24 19:09:30]

Done.

+#include "net/url_request/request_throttler_header_interface.h"
+
+// Adapter for the HTTP header interface of the request throttler component.
+class RequestThrottlerHeaderAdapter : public RequestThrottlerHeaderInterface {
+ public:
+  explicit RequestThrottlerHeaderAdapter(net::HttpResponseHeaders* headers);
+  virtual ~RequestThrottlerHeaderAdapter() {}
+
+  // Implementation of RequestThrottlerHeaderInterface
+  virtual std::string GetNormalizedValue(const std::string& key) const;
+  virtual int GetResponseCode() const;
+
+ private:
+  const scoped_refptr<net::HttpResponseHeaders> response_header_;
+};
+
+#endif  // NET_URL_REQUEST_REQUEST_THROTTLER_HEADER_ADAPTER_H_