Use the suggested name from an anchor's 'download' attribute.

chrome/browser/download/download_util.cc

 // 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.
 //
 // Download utility implementation
 
 #include "chrome/browser/download/download_util.h"
 
 #if defined(OS_WIN)
 #include <shobjidl.h>
@@ skipping 270 matching lines @@
     // The GetPreferredExtensionForMimeType call will end up going to disk.  Do
     // this on another thread to avoid slowing the IO thread.
     // http://crbug.com/61827
     base::ThreadRestrictions::ScopedAllowIO allow_io;
     net::GetPreferredExtensionForMimeType(mime_type, &extension);
   }
 
   generated_extension->swap(extension);
 }
 
-void GenerateFileNameFromRequest(const GURL& url,
-                                 const std::string& content_disposition,
-                                 const std::string& referrer_charset,
-                                 const std::string& mime_type,
+void GenerateFileNameFromRequest(const DownloadItem& download_item,
                                  FilePath* generated_name) {
-  GenerateFileNameInternal(url,
-                           content_disposition,
-                           referrer_charset,
-                           std::string(),
-                           mime_type,
+  GenerateFileNameInternal(download_item.GetURL(),
+                           download_item.content_disposition(),
+                           download_item.referrer_charset(),
+                           download_item.suggested_filename(),
+                           download_item.mime_type(),
                            generated_name);
 }
 
 void GenerateFileNameFromSuggestedName(const GURL& url,
                                        const std::string& suggested_name,
                                        const std::string& mime_type,
                                        FilePath* generated_name) {
   GenerateFileNameInternal(url, std::string(), std::string(),
                            suggested_name, mime_type, generated_name);
 }
@@ skipping 601 matching lines @@
 FilePath GetCrDownloadPath(const FilePath& suggested_path) {
   FilePath::StringType file_name;
   base::SStringPrintf(
       &file_name,
       PRFilePathLiteral FILE_PATH_LITERAL(".crdownload"),
       suggested_path.value().c_str());
   return FilePath(file_name);
 }
 
 }  // namespace download_util