Serializes if message is a google.protobuf.Any field.

def _TryPrintAsAnyMessage(self, message):
    """Serializes if message is a google.protobuf.Any field."""
    packed_message = _BuildMessageFromTypeName(message.TypeName(),
                                               self.descriptor_pool)
    if packed_message:
      packed_message.MergeFromString(message.value)
      self.out.write('%s[%s]' % (self.indent * ' ', message.type_url))
      self._PrintMessageFieldValue(packed_message)
      self.out.write(' ' if self.as_one_line else '\n')
      return True
    else:
      return False