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

net/data/proxy_resolver_v8_unittest/dns_fail.js

+// This script should be run in an environment where all DNS resolution are
+// failing. It tests that functions return the expected values.
+//
+// Returns "PROXY success:80" on success.
+function FindProxyForURL(url, host) {
+  try {
+    expectEq("127.0.0.1", myIpAddress());
+    expectEq("", myIpAddressEx());
+
+    expectEq(null, dnsResolve("not-found"));
+    expectEq("", dnsResolveEx("not-found"));
+
+    expectEq(false, isResolvable("not-found"));
+    expectEq(false, isResolvableEx("not-found"));
+
+    return "PROXY success:80";
+  } catch(e) {
+    alert(e);
+    return "PROXY failed:80";
+  }
+}
+
+function expectEq(expected, actual) {
+  if (expected != actual)
+    throw "Expected " + expected + " but was " + actual;
+}
+