Update
A ready-to-use element for Dart Polymer 1.0 is bwu-bind-html
{{}}
can't include HTML.
You can use something like the <safe-html>
tag (see answer to HTML Tags Within Internationalized Strings In Polymer.dart)
<template repeat="{{element in elements}}">
<safe-html model="{{element.SOMETHING}}"></safe-html>
</template>
but I guess you have to change the <self-html>
implementation so that it replaces itself with the content of model
instead of adding model
to it's content, because ul
/ol
can't contain <self-html>