Always treat .localhost as loopback

net/dns/dns_transaction.cc

Index: net/dns/dns_transaction.cc
diff --git a/net/dns/dns_transaction.cc b/net/dns/dns_transaction.cc
index beb2197dd55b7bc50d39c71cb70d46c29bfd2a77..73a2c40e4b41864f4ef7c43ab064f9708fbb2e4f 100644
--- a/net/dns/dns_transaction.cc
+++ b/net/dns/dns_transaction.cc
@@ -28,6 +28,7 @@
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
+#include "net/base/net_util.h"
 #include "net/dns/dns_protocol.h"
 #include "net/dns/dns_query.h"
 #include "net/dns/dns_response.h"
@@ -616,12 +617,16 @@ class DnsTransactionImpl : public DnsTransaction,
   // Prepares |qnames_| according to the DnsConfig.
   int PrepareSearch() {
     const DnsConfig& config = session_->config();
+    // Redirect .localhost queries to localhost to make sure that they are

[Deprecated (see juliatuttle), 2015/02/24 16:39:23]

Nit: "to localhost.", since you're including the trailing dot.

[estark, 2015/02/26 07:58:53]

fixed in the place where this comment has been relocated to

+    // never sent out on the network, per RFC 6761.
+    const std::string hostname =
+        (IsLocalhostTLD(hostname_) ? "localhost." : hostname_);
 
     std::string labeled_hostname;
-    if (!DNSDomainFromDot(hostname_, &labeled_hostname))
+    if (!DNSDomainFromDot(hostname, &labeled_hostname))
       return ERR_INVALID_ARGUMENT;
 
-    if (hostname_[hostname_.size() - 1] == '.') {
+    if (hostname[hostname.size() - 1] == '.') {
       // It's a fully-qualified name, no suffix search.
       qnames_.push_back(labeled_hostname);
       return OK;
@@ -645,7 +650,7 @@ class DnsTransactionImpl : public DnsTransaction,
     std::string qname;
     for (size_t i = 0; i < config.search.size(); ++i) {
       // Ignore invalid (too long) combinations.
-      if (!DNSDomainFromDot(hostname_ + "." + config.search[i], &qname))
+      if (!DNSDomainFromDot(hostname + "." + config.search[i], &qname))
         continue;
       if (qname.size() == labeled_hostname.size()) {
         if (had_hostname)