Does Google's webcrawler follow HTML imports?

I've tested with "Fetch as Google" in the webmaster Search Console. The screenshots show that the imports are being loaded and shown exactly as a normal user would see them.

The question still remains though: is the imported HTML indexed?

I've requested google to index the page. And will report back when it has been indexed.

Reporting back: the contents of the imported page is indeed indexed as like it was contents of the parent page. I see imported content in the snippet on the search results page! Even the title of the imported page is shown as title of the search result!

This is big news, right?

You could always check what your site looks like to googlebot: https://support.google.com/webmasters/answer/6066468?rd=2 and to be sure look at the access logs of your server.

There doesn't seem to be any information on the engine used w/i googlebot but if it's Chrome 36+ it will work. Alternatively, you could use webcompontent.js Polyfills at http://webcomponents.org/polyfills/ which should work.