HtmlFile:test.html
  PsiElement(HTML_DOCUMENT)
    PsiElement(XML_PROLOG)
      <empty list>
    HtmlTag:a
      XmlToken:XML_START_TAG_START('<')
      XmlToken:XML_NAME('a')
      XmlToken:XML_TAG_END('>')
      PsiElement(XML_PROCESSING_INSTRUCTION)
        XmlToken:XML_PI_START('<?')
        XmlToken:XML_PI_TARGET('This is="PI"')
        XmlToken:XML_PI_END('?>')
      XmlToken:XML_END_TAG_START('</')
      XmlToken:XML_NAME('a')
      XmlToken:XML_TAG_END('>')