I hate to report old news, but this is old news and IMHO there's no workaround. The only option you'll have is to put the location in the "Notes" field - Google Calendar will mostly "figure out" the location and convert it into a URL in your Google Calendar. Google's Calendar and iOS Calendar app don't map directly field-to-field - a lament of iOS users going back several years. Maybe there's a fix someone else knows about, but I'd hazard a guess that it's pretty much not changed...
I used to use Google Apps, that's the way it worked - and I switched to Exchange because the rest of my world (clients/consultants) were tired of the URL conversion and having to enter in locations/resources (rooms, buildings, etc.) correctly, and let me know about it. Cheers!