Setting the policy specifies which servers should be allowed for integrated authentication. Integrated authentication is only on when Google Chrome gets an authentication challenge from a proxy or from a server in this permitted list.
Leaving the policy unset means Google Chrome tries to detect if a server is on the intranet. Only then will it respond to IWA requests. If a server is detected as internet, then Google Chrome ignores IWA requests from it.
Note: Separate multiple server names with commas. Wildcards, *, are allowed.
Example value: *.example.com,example.com