Using the SharePoint Online REST API, I'm trying to retrieve a list of all sites *and* subsites.

This API gives me all top level sites, but no subsites:

    https://{mycompany}.sharepoint.com/_api/search/query?querytext='contentclass:sts_site'

This API gives me all sub-sites of the root top level site:

    https://{mycompany}.sharepoint.com/_api/search/query?querytext='*'&trim&refinementfilters='contentclass:equals("STS_Web")'

I'd like a **single query** which retrieves all sites *and* all of their subsites --
not just subsites of the root site.