Bug 607265 - 'mailnews.use_received_date' pref is no longer used, should be removed; r=bienvenu

mailnews/mailnews.js

@@ -709,8 +709,6 @@ pref("mail.server.default.retainBy", 1);
 pref("mailnews.ui.junk.firstuse", true);
 pref("mailnews.ui.junk.manualMarkAsJunkMarksRead", true);
 
-pref("mailnews.use_received_date", false);
-
 // for manual upgrades of certain UI features.
 // 1 -> 2 is for the folder pane tree landing, to hide the
 // unread and total columns, see msgMail3PaneWindow.js