Improve performance of proxy resolver by tracing DNS dependencies.

net/data/proxy_resolver_v8_tracing_unittest/dns_during_init.js

Index: net/data/proxy_resolver_v8_tracing_unittest/dns_during_init.js
diff --git a/net/data/proxy_resolver_v8_tracing_unittest/dns_during_init.js b/net/data/proxy_resolver_v8_tracing_unittest/dns_during_init.js
new file mode 100644
index 0000000000000000000000000000000000000000..55aef52e6f13b57632337878a79a62662b4782ab
--- /dev/null
+++ b/net/data/proxy_resolver_v8_tracing_unittest/dns_during_init.js
@@ -0,0 +1,14 @@
+var g_ips = [
+  dnsResolve('host1'),
+  dnsResolve('host2')
+];
+
+alert('Watsup');
+alert('Watsup2');
+
+function FindProxyForURL(url, host) {
+  // Note that host1 and host2 should not resolve using the same cache as was
+  // used for g_ips!
+  var ips = g_ips.concat([dnsResolve('host1'), dnsResolve('host2')]);
+  return 'PROXY ' + ips.join('-') + ':99';
+}