Place source URL of DownloadFile in extended attributes

content/browser/download/file_metadata_linux.h

Index: content/browser/download/file_metadata_linux.h
===================================================================
--- content/browser/download/file_metadata_linux.h	(revision 0)
+++ content/browser/download/file_metadata_linux.h	(revision 0)
@@ -0,0 +1,31 @@
+// 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_DOWNLOAD_FILE_METADATA_LINUX_H_
+#define CONTENT_BROWSER_DOWNLOAD_FILE_METADATA_LINUX_H_
+
+#include "content/common/content_export.h"
+
+class FilePath;
+class GURL;
+
+namespace file_metadata {

[darin (slow to review), 2012/07/25 18:25:19]

nit: this shouldn't be in its own namespace:

From the style guide:
"With named namespaces, choose the name based on the project, and possibly its
path."

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Namesp...

+
+// The source URL attribute is part of the XDG standard.
+// The referrer URL attribute is not part of the XDG standard,
+// but it is used to keep the naming consistent.
+// http://freedesktop.org/wiki/CommonExtendedAttributes
+CONTENT_EXPORT extern const char kSourceURLAttrName[];
+CONTENT_EXPORT extern const char kReferrerURLAttrName[];
+
+// Adds origin metadata to the file.
+// |source| should be the source URL for the download, and |referrer| should be
+// the URL the user initiated the download from.
+CONTENT_EXPORT void AddOriginMetadataToFile(const FilePath& file,
+                                            const GURL& source,
+                                            const GURL& referrer);
+
+}  // namespace file_metadata
+
+#endif  // CONTENT_BROWSER_DOWNLOAD_FILE_METADATA_LINUX_H_