Making variations to the search results pages, Google has now announced the change in the appearance of the domain portion of the URLs. It will be now shown in lowercases.
For eg, if the display URL is Subdomain.Example.com/Subdirectory, it will appear as subdomain.example.com/Subdirectory.
No edit is required at the user's end. All uppercases will automatically change to lower cases when the ad is served.