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

chrome/browser/download/download_item.h

 // 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.
 //
 // Each download is represented by a DownloadItem, and all DownloadItems
 // are owned by the DownloadManager which maintains a global list of all
 // downloads. DownloadItems are created when a user initiates a download,
 // and exist for the duration of the browser life time.
 //
 // Download observers:
@@ skipping 248 matching lines @@
   DownloadState state() const { return state_; }
   const FilePath& full_path() const { return full_path_; }
   void set_path_uniquifier(int uniquifier) {
     state_info_.path_uniquifier = uniquifier;
   }
   const GURL& GetURL() const;
 
   const std::vector<GURL>& url_chain() const { return url_chain_; }
   const GURL& original_url() const { return url_chain_.front(); }
   const GURL& referrer_url() const { return referrer_url_; }
+  std::string suggested_filename() const { return suggested_filename_; }
   std::string content_disposition() const { return content_disposition_; }
   std::string mime_type() const { return mime_type_; }
   std::string original_mime_type() const { return original_mime_type_; }
   std::string referrer_charset() const { return referrer_charset_; }
   int64 total_bytes() const { return total_bytes_; }
   void set_total_bytes(int64 total_bytes) {
     total_bytes_ = total_bytes;
   }
   int64 received_bytes() const { return received_bytes_; }
   int32 id() const { return download_id_; }
@@ skipping 108 matching lines @@
   // A number that should be appended to the path to make it unique, or 0 if the
   // path should be used as is.
   int path_uniquifier_;
 
   // The chain of redirects that leading up to and including the final URL.
   std::vector<GURL> url_chain_;
 
   // The URL of the page that initiated the download.
   GURL referrer_url_;
 
+  // Suggested filename in 'download' attribute of an anchor. Details:
+  // http://www.whatwg.org/specs/web-apps/current-work/#downloading-hyperlinks
+  std::string suggested_filename_;
+
   // Information from the request.
   // Content-disposition field from the header.
   std::string content_disposition_;
 
   // Mime-type from the header.  Subject to change.
   std::string mime_type_;
 
   // The value of the content type header sent with the downloaded item.  It
   // may be different from |mime_type_|, which may be set based on heuristics
   // which may look at the file extension and first few bytes of the file.
@@ skipping 70 matching lines @@
   // only.
   bool open_enabled_;
 
   // DownloadItem observes CRX installs it initiates.
   NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadItem);
 };
 
 #endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_ITEM_H_