Find highlight not available on readonly elements.

[Garry Yao]

1. Load the editor with the following content:

   <p contenteditable="false">inside read-only paragraph</p>
   

2. Open find dialog and search for "read-only"
   • Actual Result: When clicking on "Find" button the word matched is not highlighted.

[Jakub Ś]

This summary should rather sound:
JS error thrown when searching for text in read-only elements.

I did not encounter any highlight problems but form CKEditor 3.5 when you try to search for text that is inside read-only element the JS error is thrown.

Message: currentNode is null
Line: 455
URI: /ckeditor/_source/plugins/styles/plugin.js

[Wiktor Walc]

Oops, as a result it's impossible to close the dialog.

In any case, it's a duplicate of #6957.