Bug 496273: Cannot unsubscribe newsgroup (Error: server is undefined). r=standard8

mail/base/content/folderPane.js

@@ -1547,8 +1547,8 @@ let gFolderTreeController = {
     let folder = folders[0];
 
     // For newsgroups, "delete" means "unsubscribe".
-    if (folder.server.type == "nntp" && ConfirmUnsubscribe(folders)) {
-      Unsubscribe(folders);
+    if (folder.server.type == "nntp") {
+      MsgUnsubscribe(folders);
       return;
     }
 

mail/base/content/mailCommands.js

@@ -310,17 +310,6 @@ function NewFolder(name, folder)
   folder.createSubfolder(name, msgWindow);
 }
 
-function UnSubscribe(folder)
-{
-  // Unsubscribe the current folder from the newsserver, this assumes any confirmation has already
-  // been made by the user  SPL
-
-  var server = folder.server;
-  var subscribableServer = server.QueryInterface(Components.interfaces.nsISubscribableServer);
-  subscribableServer.unsubscribe(folder.name);
-  subscribableServer.commitSubscribeChanges();
-}
-
 function Subscribe(preselectedMsgFolder)
 {
   window.openDialog("chrome://messenger/content/subscribe.xul",

mail/base/content/mailWindowOverlay.js

@@ -1597,13 +1597,21 @@ function ConfirmUnsubscribe(folders)
 }
 
 /**
- * Unsubscribe from selected newsgroup/s.
+ * Unsubscribe from selected or passed in newsgroup/s.
+ * @param newsgroups (optional param) the newsgroup folders to unsubscribe from
  */
-function MsgUnsubscribe()
+function MsgUnsubscribe(newsgroups)
 {
-  var folders = gFolderTreeView.getSelectedFolders();
-  if (ConfirmUnsubscribe(folders))
-    UnSubscribe(folders);
+  var folders = newsgroups || gFolderTreeView.getSelectedFolders();
+  if (!ConfirmUnsubscribe(folders))
+    return;
+
+  for (let i = 0; i < folders.length; i++) {
+    let subscribableServer = folders[i].server.QueryInterface(
+      Components.interfaces.nsISubscribableServer);
+    subscribableServer.unsubscribe(folders[i].name);
+    subscribableServer.commitSubscribeChanges();
+  }
 }
 
 function ToggleFavoriteFolderFlag()