GitLab

This changes the template stamping parts of cr-lazy-render to look more
like iron-list. This simplifies the code and makes it play nicely with
Closure.

BUG=642200
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2344803002
Cr-Commit-Position: refs/heads/master@{#419058}