Implement select listbox using shadow DOM

Source/core/editing/TextIterator.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 887 matching lines @@
             || node.hasTagName(hrTag)
             || node.hasTagName(liTag)
             || node.hasTagName(listingTag)
             || node.hasTagName(olTag)
             || node.hasTagName(pTag)
             || node.hasTagName(preTag)
             || node.hasTagName(trTag)
             || node.hasTagName(ulTag));
     }
 
+    // Need to make an exception for option and optgroup, because we want to
+    // keep the legacy behavior before we added renderers to them.
+    if (isHTMLOptionElement(node) || isHTMLOptGroupElement(node))
+        return false;
+
     // Need to make an exception for table cells, because they are blocks, but we
     // want them tab-delimited rather than having newlines before and after.
     if (isTableCell(&node))
         return false;
 
     // Need to make an exception for table row elements, because they are neither
     // "inline" or "RenderBlock", but we want newlines for them.
     if (r->isTableRow()) {
         RenderTable* t = toRenderTableRow(r)->table();
         if (t && !t->isInline())
@@ skipping 1296 matching lines @@
             resultEnd = collapseTo;
             return;
         }
     }
 
     CharacterIterator computeRangeIterator(inputStart, inputEnd, iteratorFlagsForFindPlainText);
     calculateCharacterSubrange(computeRangeIterator, matchStart, matchLength, resultStart, resultEnd);
 }
 
 }