     /**
      *  @private
      */
+    mx_internal function createEmptyTextLine(height:Number=NaN):void
+    {
+        // override this
+    }
+    
+    /**
+     *  @private
+     */
     mx_internal function invalidateTextLines():void
     {
         invalidateCompose = true;

    {
        if (!validateBaselinePosition())
            return NaN;
        
        // Return the baseline of the first line of composed text.
        return textLines.length > 0 ? textLines[0].y : 0;

		if (n == 0)
			return;

		for (var i:int = 0; i < n; i++)
		{
			var textLine:DisplayObject = textLines[i];	
            var parent:UIComponent = textLine.parent as UIComponent;
            if (parent)
                UIComponent(textLine.parent).$removeChild(textLine);
		}
	}

