Codesnippet checkDirty is true after modify code and then rollback

[Artur Delura]

1. Open code snippet sample with following code i.e. you must modify sample source.

   <pre>
   <code class="language-javascript">a;
   </code></pre>
   
   
   <pre>
   <code class="language-sql">a;
   </code></pre>
   

2. Double click on first codesnippet widget, to open dialog.
3. Remove ; and apply.
4. Open codesnippet dialog again and rollback changes. Add ; sign where it was.
5. Apply changes.

Actual result: Calling method CKEDITOR.instances.editor1.getSnapshot(); return false

Please note: This happend only when there are two codesnippet widgets.