Reduce allocations from computing item property (#8485)
Reduce allocations from computing item property (#8485)

Merge pull request 8485
ryanshaw/jekyll,jaybe-jekyll/jekyll,jaybe-jekyll/jekyll,fulldecent/jekyll,fulldecent/jekyll,ryanshaw/jekyll,jaybe-jekyll/jekyll,chrisfinazzo/jekyll,fulldecent/jekyll,chrisfinazzo/jekyll,x-way/jekyll,jekyll/jekyll,x-way/jekyll,chrisfinazzo/jekyll,ryanshaw/jekyll,jekyll/jekyll,jekyll/jekyll,x-way/jekyll,fulldecent/jekyll,jaybe-jekyll/jekyll,jekyll/jekyll,ryanshaw/jekyll,x-way/jekyll,chrisfinazzo/jekyll