Add mime type information to the download database

chrome/browser/history/download_row.h

Index: chrome/browser/history/download_row.h
diff --git a/chrome/browser/history/download_row.h b/chrome/browser/history/download_row.h
index d38eec5268bb62664d0b7bcd9167121a611a09bb..0828abf44c67f4628244ac8a07aff2a99744b5a4 100644
--- a/chrome/browser/history/download_row.h
+++ b/chrome/browser/history/download_row.h
@@ -5,6 +5,7 @@
 #ifndef CHROME_BROWSER_HISTORY_DOWNLOAD_ROW_H_
 #define CHROME_BROWSER_HISTORY_DOWNLOAD_ROW_H_
 
+#include <string>
 #include <vector>
 
 #include "base/files/file_path.h"
@@ -26,6 +27,8 @@ struct DownloadRow {
       const base::FilePath& target_path,
       const std::vector<GURL>& url_chain,
       const GURL& referrer,
+      const std::string& mime_type,
+      const std::string& original_mime_type,
       const base::Time& start,
       const base::Time& end,
       const std::string& etag,
@@ -57,6 +60,12 @@ struct DownloadRow {
   // The URL that referred us. Is not changed by UpdateDownload().
   GURL referrer_url;
 
+  // The mime type of the download, might be based on heuristics.
+  std::string mime_type;

[sky, 2013/12/18 23:24:05]

If this is based on heuristics, how come it needs to be cached? That is, can't
we calculated it as needed?

+
+  // The originial mime type of the download.
+  std::string original_mime_type;

[sky, 2013/12/18 23:24:05]

How about coverage that mime_type and original_mime_type are persisted/fetched
appropriately from db?

+
   // The time when the download started. Is not changed by UpdateDownload().
   base::Time start_time;