Fast-fail WPAD detection.

net/dns/host_resolver_impl_unittest.cc

Index: net/dns/host_resolver_impl_unittest.cc
diff --git a/net/dns/host_resolver_impl_unittest.cc b/net/dns/host_resolver_impl_unittest.cc
index 24a00a9d69e59ffe9aa5481076dbc4337e2da0fc..c314f80c24d0e7dcb0af2f2c9616b055036e664d 100644
--- a/net/dns/host_resolver_impl_unittest.cc
+++ b/net/dns/host_resolver_impl_unittest.cc
@@ -1563,6 +1563,24 @@ TEST_F(HostResolverImplDnsTest, BypassDnsTask) {
     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
 }
 
+TEST_F(HostResolverImplDnsTest, SystemOnlyBypassesDnsTask) {
+  ChangeDnsConfig(CreateValidDnsConfig());
+
+  proc_->AddRuleForAllFamilies(std::string(), std::string());
+
+  HostResolver::RequestInfo info_bypass(HostPortPair("ok", 80));
+  info_bypass.set_host_resolver_flags(HOST_RESOLVER_SYSTEM_ONLY);
+  EXPECT_EQ(ERR_IO_PENDING, CreateRequest(info_bypass, MEDIUM)->Resolve());
+
+  HostResolver::RequestInfo info(HostPortPair("ok", 80));
+  EXPECT_EQ(ERR_IO_PENDING, CreateRequest(info, MEDIUM)->Resolve());
+
+  proc_->SignalMultiple(requests_.size());
+
+  EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[0]->WaitForResult());
+  EXPECT_EQ(OK, requests_[1]->WaitForResult());
+}
+
 TEST_F(HostResolverImplDnsTest, DisableDnsClientOnPersistentFailure) {
   ChangeDnsConfig(CreateValidDnsConfig());