Google seems to be testing showing a Google Shopping logo or label on some search results that may be considered a Top Quality Store in Google's Merchant Center program. This label is added to the top right section of the site name, above the URL.
Brodie Clark posted about this on Twitter and wrote, "In a continuation of recently testing related to Top Quality Store's on Google, another mobile test has appeared which only features a Google Shopping icon beside the Site Name. Different to the other tests, this icon does not link anywhere."
Here is his screenshot:
Forum discussion at Twitter.