Undo save: optional add operation

app/src/main/java/eu/faircode/email/ActivityCompose.java

@@ -294,6 +294,9 @@ public class ActivityCompose extends ActivityBase implements FragmentManager.OnB
     static Long undoSend(long id, Context context) {
         DB db = DB.getInstance(context);
 
+        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
+        boolean save_drafts = prefs.getBoolean("save_drafts", true);
+
         // Cancel send
         EntityOperation operation = db.operation().getOperation(id, EntityOperation.SEND);
         if (operation != null)
@@ -336,7 +339,10 @@ public class ActivityCompose extends ActivityBase implements FragmentManager.OnB
             for (EntityAttachment attachment : attachments)
                 db.attachment().setMessage(attachment.id, message.id);
 
-            EntityOperation.queue(context, message, EntityOperation.ADD);
+            if (save_drafts &&
+                    (message.ui_encrypt == null ||
+                            EntityMessage.ENCRYPT_NONE.equals(message.ui_encrypt)))
+                EntityOperation.queue(context, message, EntityOperation.ADD);
 
             // Delete from outbox
             db.message().deleteMessage(id); // will delete operation too