Fix height on demo iframe
Fix height on demo iframe

eliotsykes/ember-community-versions,steveklabnik/rust-community-versions,jgwhite/ember-community-versions,mixonic/ember-community-versions,balinterdi/ember-community-versions,greyhwndz/ember-community-versions,dukex/ember-community-versions,vanjacosic/django-community-versions,cball/ember-community-versions,alexdiliberto/ember-community-versions