public/ckeditor/4.4dev/core/dom/element.js
function( selector ) {
			var removeTmpId = createTmpId( this ),
				found = this.$.querySelector( getContextualizedSelector( this, selector ) );

			removeTmpId();

			return found ? new CKEDITOR.dom.element( found ) : null;
		}
function( selector ) {
			var removeTmpId = createTmpId( this ),
				found = this.$.querySelector( getContextualizedSelector( this, selector ) );

			removeTmpId();

			return found ? new CKEDITOR.dom.element( found ) : null;
		}
function ( selector ) { var removeTmpId = createTmpId ( this ) , found = this . $ . querySelector ( getContextualizedSelector ( this , selector ) ) ; removeTmpId ( ) ; return found ? new CKEDITOR . dom . element ( found ) : null ; }
Returns first element within this element that matches specified `selector`.

**Notes:**

* Not available in IE7.
* Unlike native `querySelectorAll` this method ensures selector contextualization. This is:

HTML:		'<body><div><i>foo</i></div></body>'
Native:		div.querySelector( 'body i' ) // ->			<i>foo</i>
Method:		div.findOne( 'body i' ) // ->				null
div.findOne( 'i' ) // ->					<i>foo</i>

@since 4.3
@param {String} selector
@returns {CKEDITOR.dom.element}
Returns first element within this element that matches specified selector .