Linux Mac OSX Windows 
 This interface servers as a closure for nsIProtocolProxyService's
 asyncResolve method.

 @status UNDER_REVIEW
[scriptable, uuid(a9967200-f95e-45c2-beb3-9b060d874bfd)]
interface nsIProtocolProxyCallback : nsISupports

Methods

 This method is called when proxy info is available or when an error
 in the proxy resolution occurs.

 @param aRequest
        The value returned from asyncResolve.
 @param aURI
        The URI passed to asyncResolve.
 @param aProxyInfo
        The resulting proxy info or null if there is no associated proxy
        info for aURI.  As with the result of nsIProtocolProxyService's
        resolve method, a null result implies that a direct connection
        should be used.
 @param aStatus
        The status of the callback.  This is a failure code if the request
        could not be satisfied, in which case the value of aStatus
        indicates the reason for the failure.
void onProxyAvailable(in nsICancelable aRequest, in nsIURI aURI, in nsIProxyInfo aProxyInfo, in nsresult aStatus)