can't use right arrow key to bypass the form elements ( checkbox or radio)

[brooks]

when the last element of the edit doc is checkbox or radio, can't bypass it use right arrow key. that means we can't add content after the form element.

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reproduce

1. enter this code in source view.

   <p>test<input name="ddd" type="checkbox" /></p>
   

2. turn to WYSIWYG mode,and press right arrow key to reach the position after checkbox.
   

expect result: the cursor is blinking after checkbox
real result: the cursor only can reach the position before checkbox,we can't go further any more.

confirmed in

1. win7, IE8 mode( IE8 compatible mode is ok )
   
2. win7, firefox2.0 ( firefox3.5 is available,thought can't let the cursor blinking after checkbox, but you can add content after it)

[Frederico Caldeira Knabben]

Milestone CKEditor 3.x deleted

[Jakub Ś]

This is a duplicate of #3513.