Prevent closing draft

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

@@ -382,6 +382,8 @@ class Core {
 
         // Delete previous message(s) with same ID
         if (folder.id.equals(message.folder)) {
+            db.message().setMessageUid(message.id, null);
+
             Message[] ideletes = ifolder.search(new MessageIDTerm(message.msgid));
             for (Message idelete : ideletes) {
                 long uid = ifolder.getUID(idelete);

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

@@ -271,7 +271,7 @@ public interface DaoMessage {
     int setMessageFolder(long id, long folder);
 
     @Query("UPDATE message SET uid = :uid WHERE id = :id")
-    int setMessageUid(long id, long uid);
+    int setMessageUid(long id, Long uid);
 
     @Query("UPDATE message SET seen = :seen WHERE id = :id")
     int setMessageSeen(long id, boolean seen);