The file target-utils.js, located under cordova/lib, is used to get information a about the devices, emulators, even if those are registered in the blackberry10.json file.
When a cordova application is created, build and then deployed into the blackberry emulator or device, all records stays at the blackberry10.json file, that information include description, ip, pin, and type. When emulate, it sets 'emulator', target-utils.js it looks for this file and check the content, and it's looking for the word 'simulator', so it won't work anymore if this word is not chaged, and replaced for 'emulator'.
Besides, from this change it depends this issue: https://issues.apache.org/jira/browse/CB-6121
The cordova info command it will use the target-utils.js, to add support for blackberry10.