#each doesn't work with null values that change to a can.List

[justinbmeyer]

var template = can.stache("<ul>{{#each items}}<li>{{name}}</li>{{/each}}");
        var data = new can.Map({items: null});
        var frag = template(data);

        var div = document.createElement("div");
        div.appendChild(frag);


        data.attr("items", [{name: "foo"}]);

        equal(div.getElementsByTagName("li").length, 1, "li added");

[justinbmeyer]

This is related to #629.

[justinbmeyer]

@hurgleburgler Can you and @daffl get this in for 2.2 this week? Is there a pull request for this?