Generate string matching state rules.

def GenQuotedState(self):
    """Generate string matching state rules."""
    for i, q in enumerate(self.quot):
      label = "%s_STRING" % i
      escaped = re.escape(q)
      self._AddToken(label, escaped, "PopState", None)
      self._AddToken(label, q, "PopState", None)
      if self.ml_quote:
        self._AddToken(label, r"\n", None, None)
      else:
        self._AddToken(label, r"\n", "BadLine", None)
      self._AddToken(label, ".", "AddToField", None)