Series of *UNTESTED* changes that should move the internal structure of

a message from a string to an email object that is part of the built-in
email library.  The allows for emails to be processed as bytes and
re-encoded properly if they are not UTF-8 or ascii encoded.  Currently
these changes cover the Base, IMAP, and Maildir classes but not the
specialized GMAIL class yet.

offlineimap/ui/UIBase.py

@@ -266,7 +266,7 @@ class UIBase:
                           (self.getnicename(x), x.getname()) for x in folder_list])
 
     # WARNINGS
-    def msgtoreadonly(self, destfolder, uid, content, flags):
+    def msgtoreadonly(self, destfolder, uid):
         if self.config.has_option('general', 'ignore-readonly') and \
                 self.config.getboolean('general', 'ignore-readonly'):
             return