Propagate the encoded data length through OnDownloadData delegate method

content/common/resource_messages.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.
 
 // IPC messages for resource loading.
 //
 // NOTE: All messages must send an |int request_id| as their first parameter.
 
 // Multiply-included message file, hence no include guard.
 #include "base/memory/shared_memory.h"
@@ skipping 237 matching lines @@
 // SetDataBuffer message.
 IPC_MESSAGE_ROUTED4(ResourceMsg_DataReceived,
                     int /* request_id */,
                     int /* data_offset */,
                     int /* data_length */,
                     int /* encoded_data_length */)
 
 // Sent when some data from a resource request has been downloaded to
 // file. This is only called in the 'download_to_file' case and replaces
 // ResourceMsg_DataReceived in the call sequence in that case.
-IPC_MESSAGE_ROUTED2(ResourceMsg_DataDownloaded,
+IPC_MESSAGE_ROUTED3(ResourceMsg_DataDownloaded,
                     int /* request_id */,
-                    int /* data_len */)
+                    int /* data_len */,
+                    int /* encoded_data_length */)
 
 // Sent when the request has been completed.
 IPC_MESSAGE_ROUTED5(ResourceMsg_RequestComplete,
                     int /* request_id */,
                     int /* error_code */,
                     bool /* was_ignored_by_handler */,
                     std::string /* security info */,
                     base::TimeTicks /* completion_time */)
 
 // Resource messages sent from the renderer to the browser.
@@ skipping 35 matching lines @@
                     int /* request_id */)
 
 // Sent when the renderer process deletes a resource loader.
 IPC_MESSAGE_CONTROL1(ResourceHostMsg_ReleaseDownloadedFile,
                      int /* request_id */)
 
 // Sent by the renderer when a resource request changes priority.
 IPC_MESSAGE_ROUTED2(ResourceHostMsg_DidChangePriority,
                     int /* request_id */,
                     net::RequestPriority)