Fix issue #1176: Can't change table engine after creation. Seems a TCombobox.OnChange is not fired if a OnSelect coexists.

source/table_editor.dfm

@@ -368,7 +368,6 @@ object frmTableEditor: TfrmTableEditor
         Anchors = [akLeft, akTop, akRight]
         ItemHeight = 0
         TabOrder = 6
-        OnChange = Modification
         OnSelect = comboEngineSelect
       end
       object chkCharsetConvert: TCheckBox

source/table_editor.pas

@@ -1081,6 +1081,7 @@ begin
   IsMerge := (Sender as TComboBox).Text = 'MRG_MYISAM';
   memoUnionTables.Enabled := IsMerge;
   comboInsertMethod.Enabled := IsMerge;
+  Modification(Sender);
 end;