added a silent member. sr=attinasi r=kmmclusk.

gfx/idl/nsIPrintOptions.idl

@@ -134,6 +134,8 @@ interface nsIPrintOptions : nsISupports
   attribute short   howToEnableFrameUI;
   attribute short   printFrameType;
   attribute boolean isCancelled;
+  attribute boolean printSilent;	/* print without putting up the dialog */
+
 
   /* Additional XP Related */
   attribute boolean printReversed;