Radio inputs are focusable which makes possible to navigate past alignment group in Image2 dialog.
Added role="radiogroup" to radios container with aria-labelledby to improve a11y.
Slight code-style fix and re-indenting of CKEDITOR.ui.dialog.radio.
Removed unusded commonAttributes variable from CKEDITOR.ui.dialog.radio, code simplification.
Changelog entry.
Merge branch 't/10866' into major