nsIWebProgressListener2 in Firefox 2.0

 Notification that the progress has changed for one of the requests
 associated with aWebProgress.  Progress totals are reset to zero when all
 requests in aWebProgress complete (corresponding to onStateChange being
 called with aStateFlags including the STATE_STOP and STATE_IS_WINDOW
 flags).

 This function is identical to nsIWebProgressListener::onProgressChange,
 except that this function supports 64-bit values.

 @param aWebProgress
        The nsIWebProgress instance that fired the notification.
 @param aRequest
        The nsIRequest that has new progress.
 @param aCurSelfProgress
        The current progress for aRequest.
 @param aMaxSelfProgress
        The maximum progress for aRequest.
 @param aCurTotalProgress
        The current progress for all requests associated with aWebProgress.
 @param aMaxTotalProgress
        The total progress for all requests associated with aWebProgress.

 NOTE: If any progress value is unknown, then its value is replaced with -1.

 @see nsIWebProgressListener2::onProgressChange64