Add three of the six extensions to PAC that Internet Explorer supports. ...

net/proxy/proxy_resolver_script.h

 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
  * 1.1 (the "License"); you may not use this file except in compliance with
  * the License. You may obtain a copy of the License at
  * http://www.mozilla.org/MPL/
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@@ skipping 245 matching lines @@
   "\n" \
   "    if (isGMT) {\n" \
   "        date.setFullYear(date.getUTCFullYear());\n" \
   "        date.setMonth(date.getUTCMonth());\n" \
   "        date.setDate(date.getUTCDate());\n" \
   "        date.setHours(date.getUTCHours());\n" \
   "        date.setMinutes(date.getUTCMinutes());\n" \
   "        date.setSeconds(date.getUTCSeconds());\n" \
   "    }\n" \
   "    return ((date1 <= date) && (date <= date2));\n" \
-  "}\n" \
+  "}\n"
+
+// This is a Microsoft extension to PAC for IPv6, see:
+// http://blogs.msdn.com/wndp/articles/IPV6_PAC_Extensions_v0_9.aspx
+#define PROXY_RESOLVER_SCRIPT_EX \
+  "function isResolvableEx(host) {\n" \
+  "    var ip = dnsResolveEx(host);\n" \

[wtc, 2009/10/24 04:40:59]

Nit: since dnsResolveEx returns all the addresses of the local host,
perhaps this variable should be named addrs or ipList.

+  "    return (ip != '');\n" \
+  "}\n"
 
 #endif  // NET_PROXY_PROXY_RESOLVER_SCRIPT_H_