Use ByteStream in downloads system to decouple source and sink.

content/browser/renderer_host/x509_user_cert_resource_handler.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_RENDERER_HOST_X509_USER_CERT_RESOURCE_HANDLER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_X509_USER_CERT_RESOURCE_HANDLER_H_
 #pragma once
 
 #include <string>
+#include <utility>
+#include <vector>
 
 #include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/ref_counted.h"
-#include "content/browser/download/download_buffer.h"
 #include "content/browser/renderer_host/resource_handler.h"
 #include "googleurl/src/gurl.h"
 
 namespace net {
 class IOBuffer;
 class URLRequest;
 class URLRequestStatus;
 }  // namespace net
 
 namespace content {
@@ skipping 39 matching lines @@
   virtual bool OnReadCompleted(int request_id,
                                int* bytes_read,
                                bool* defer) OVERRIDE;
 
   // Done downloading the certificate.
   virtual bool OnResponseCompleted(int request_id,
                                    const net::URLRequestStatus& urs,
                                    const std::string& sec_info) OVERRIDE;
 
  private:
+  typedef std::vector<std::pair<scoped_refptr<net::IOBuffer>,
+                                size_t> > ContentVector;
+
   void AssembleResource();
 
   GURL url_;
   net::URLRequest* request_;
   size_t content_length_;
   ContentVector buffer_;
   scoped_refptr<net::IOBuffer> read_buffer_;
   scoped_refptr<net::IOBuffer> resource_buffer_;  // Downloaded certificate.
   // The id of the |RenderProcessHost| which started the download.
   int render_process_host_id_;
   // The id of the |RenderView| which started the download.
   int render_view_id_;
 
   DISALLOW_COPY_AND_ASSIGN(X509UserCertResourceHandler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_X509_USER_CERT_RESOURCE_HANDLER_H_