Steps to reproduce:

1. Precondition: make connection really slow or otherwise delay response from CControllerValidateApiExists.
2. Open Host form.
3. Change name and leave the field initializing API validation request.
4. While it is in progress, press Submit.
5. Observed: First request is not canceled and is still waiting for response.
6. Expected: When submit is pressed, any existing inline validation fetch requests should be aborted.