Use FilterContext to allow filters to access URLRequestJob data...

net/url_request/url_request_simple_job.h

 // Copyright (c) 2006-2008 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_URL_REQUEST_SIMPLE_JOB_H_
 #define NET_URL_REQUEST_URL_REQUEST_SIMPLE_JOB_H_
 
+#include <string>
+
 #include "net/url_request/url_request_job.h"
 
 class URLRequest;
 
 class URLRequestSimpleJob : public URLRequestJob {
  public:
-  URLRequestSimpleJob(URLRequest* request);
+  explicit URLRequestSimpleJob(URLRequest* request);
 
   virtual void Start();
   virtual bool ReadRawData(net::IOBuffer* buf, int buf_size, int *bytes_read);
-  virtual bool GetMimeType(std::string* mime_type);
+  virtual bool GetMimeType(std::string* mime_type) const;
   virtual bool GetCharset(std::string* charset);
 
  protected:
   // subclasses must override the way response data is determined.
   virtual bool GetData(std::string* mime_type,
                        std::string* charset,
                        std::string* data) const = 0;
 
  private:
   void StartAsync();
 
   std::string mime_type_;
   std::string charset_;
   std::string data_;
   int data_offset_;
 };
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_DATA_JOB_H_