173137 r=cavin sr=bienvenu Made it so that deleting/marking read/flagged etc fails and throw

alert (only for delete) if we are compacting that folder in the background.

suite/locales/en-US/chrome/mailnews/messenger.properties

@@ -80,6 +80,7 @@ alertFilterChanged=Filters associated with this folder will be updated.
 filterDisabled=The folder '%S' could not be found, so filter(s) associated with this folder will be disabled. Verify that the folder exists, and that filters point to a valid destination folder.
 filterFolderDeniedLocked=The messages could not be filtered to folder '%S' because another operation is in progress.
 parsingFolderFailed=Unable to open the folder %S because it is in use by some other operation.Please wait for that operation to finish and then select the folder again. 
+deletingMsgsFailed=Unable to delete messages in folder %S because it is in use by some other operation. Please wait for that operation to finish and then try again.
 alertFilterCheckbox=Do not warn me again.
 compactFolderDeniedLock=The folder '%S' cannot be compacted because another operation is in progress. Please try again later.
 compactFolderWriteFailed=The folder '%S' could not be compacted because writing to folder failed. Verify that you have enough disk space, and that you have write privileges to the file system, then try again.