Change Cronet's "disable_ipv6" to "disable_ipv6_on_wifi"

net/dns/host_resolver_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_DNS_HOST_RESOLVER_IMPL_H_
 #define NET_DNS_HOST_RESOLVER_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 143 matching lines @@
                             HostCache::EntryStaleness* stale_info,
                             const NetLogWithSource& source_net_log);
 
   void InitializePersistence(
       const PersistCallback& persist_callback,
       std::unique_ptr<const base::Value> old_data) override;
 
   void SetDefaultAddressFamily(AddressFamily address_family) override;
   AddressFamily GetDefaultAddressFamily() const override;
 
+  void SetNoIPv6OnWifi() override;
+  bool GetNoIPv6OnWifi() override;
+
   void set_proc_params_for_test(const ProcTaskParams& proc_params) {
     proc_params_ = proc_params;
   }
 
  protected:
   // Just like the public constructor, but allows the task runner used for
   // blocking tasks to be specified. Intended for testing only.
   HostResolverImpl(const Options& options,
                    NetLog* net_log,
                    scoped_refptr<base::TaskRunner> worker_task_runner);
@@ skipping 75 matching lines @@
   // Returns the (hostname, address_family) key to use for |info|, choosing an
   // "effective" address family by inheriting the resolver's default address
   // family when the request leaves it unspecified.
   Key GetEffectiveKeyForRequest(const RequestInfo& info,
                                 const IPAddress* ip_address,
                                 const NetLogWithSource& net_log);
 
   // Probes IPv6 support and returns true if IPv6 support is enabled.
   // Results are cached, i.e. when called repeatedly this method returns result
   // from the first probe for some time before probing again.
-  virtual bool IsIPv6Reachable(const NetLogWithSource& net_log);
+  bool IsIPv6Reachable(const NetLogWithSource& net_log);
+
+  // Attempts to connect a UDP socket to |dest|:53. Virtual for testing.
+  virtual bool IsGloballyReachable(const IPAddress& dest,
+                                   const NetLogWithSource& net_log);
 
   // Asynchronously checks if only loopback IPs are available.
   virtual void RunLoopbackProbeJob();
 
   // Records the result in cache if cache is present.
   void CacheResult(const Key& key,
                    const HostCache::Entry& entry,
                    base::TimeDelta ttl);
 
   // Removes |job| from |jobs_|, only if it exists, but does not delete it.
@@ skipping 76 matching lines @@
   // to measure performance of DnsConfigService: http://crbug.com/125599
   bool received_dns_config_;
 
   // Number of consecutive failures of DnsTask, counted when fallback succeeds.
   unsigned num_dns_failures_;
 
   // Address family to use when the request doesn't specify one. See
   // http://crbug.com/696569 for why the option is needed.
   AddressFamily default_address_family_;
 
+  // True if IPv6 should not be attempted when on a wifi connection. See

[pauljensen, 2017/04/12 18:16:40]

nit: wifi->WiFi

[mgersh, 2017/04/12 18:26:42]

Done.

+  // http://crbug.com/696569 for further context.

[pauljensen, 2017/04/12 18:16:40]

nit: http->https

[mgersh, 2017/04/12 18:26:42]

Done.

+  bool assume_ipv6_failure_on_wifi_;
+
+  // Cache current connection type for easier testing.
+  NetworkChangeNotifier::ConnectionType current_connection_type_;

[pauljensen, 2017/04/12 18:16:40]

Can we remove this?  Caches are tricky and it doesn't look like it's actually
used for testing.

[mgersh, 2017/04/12 18:26:42]

It's actually used for testing. If I do it this way, I can tell
NetworkChangeNotifier to simulate a network change and then HostResolverImpl
thinks I'm on that kind of network. If I don't, I have to deal with mocking
NetworkChangeNotifier. Keeping it updated is one line of code.

[pauljensen, 2017/04/12 18:58:11]

How about net::test::MockNetworkChangeNotifier
(https://cs.chromium.org/chromium/src/net/quic/chromium/mock_network_change_no...

[mgersh, 2017/04/13 14:57:10]

Done.

+
   // True if DnsConfigService detected that system configuration depends on
   // local IPv6 connectivity. Disables probing.
   bool use_local_ipv6_;
 
   base::TimeTicks last_ipv6_probe_time_;
   bool last_ipv6_probe_result_;
 
   // True iff ProcTask has successfully resolved a hostname known to have IPv6
   // addresses using ADDRESS_FAMILY_UNSPECIFIED. Reset on IP address change.
   bool resolved_known_ipv6_hostname_;
@@ skipping 31 matching lines @@
 // This function is only exposed so it can be unit-tested.
 // TODO(tfarina): It would be better to change the tests so this function
 // gets exercised indirectly through HostResolverImpl.
 NET_EXPORT_PRIVATE bool ResolveLocalHostname(base::StringPiece host,
                                              uint16_t port,
                                              AddressList* address_list);
 
 }  // namespace net
 
 #endif  // NET_DNS_HOST_RESOLVER_IMPL_H_