Allow use of Mojo/V8 ProxyResolvers with URLRequestContextBuilder.

net/url_request/url_request_context_builder.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.
 
 // This class is useful for building a simple URLRequestContext. Most creators
 // of new URLRequestContexts should use this helper class to construct it. Call
 // any configuration params, and when done, invoke Build() to construct the
 // URLRequestContext. This URLRequestContext will own all its own storage.
 //
 // URLRequestContextBuilder and its associated params classes are initially
@@ skipping 94 matching lines @@
     QuicTagVector quic_connection_options;
     bool quic_close_sessions_on_ip_change;
     int quic_idle_connection_timeout_seconds;
     bool quic_migrate_sessions_on_network_change;
     bool quic_migrate_sessions_early;
     bool quic_disable_bidirectional_streams;
     bool quic_race_cert_verification;
   };
 
   URLRequestContextBuilder();
-  ~URLRequestContextBuilder();
+  virtual ~URLRequestContextBuilder();
 
   // Sets a name for this URLRequestContext. Currently the name is used in
   // MemoryDumpProvier to annotate memory usage. The name does not need to be
   // unique.
   void set_name(const char* name) { name_ = name; }
 
   // Sets whether Brotli compression is enabled.  Disabled by default;
   void set_enable_brotli(bool enable_brotli) { enable_brotli_ = enable_brotli; }
 
   // Unlike most other setters, the builder does not take ownership of the
@@ skipping 10 matching lines @@
   static void SetHttpNetworkSessionComponents(
       const URLRequestContext* context,
       HttpNetworkSession::Params* params);
 
   // These functions are mutually exclusive.  The ProxyConfigService, if
   // set, will be used to construct a ProxyService.
   void set_proxy_config_service(
       std::unique_ptr<ProxyConfigService> proxy_config_service) {
     proxy_config_service_ = std::move(proxy_config_service);
   }
+
+  // Sets the proxy service. If one is not provided, uses system libraries to

[eroman, 2017/05/16 20:21:20]

Is this comment accurate? Given that the CreateProxyService() method is virtual.

[mmenke, 2017/05/17 02:29:58]

It's accurate for the base implementation, not the subclass.  Made it clearer
that the described behavior is what's done by default, and subclasses may have
different behavior.

+  // evaluate PAC scripts, if available (And if not, skips PAC resolution).
   void set_proxy_service(std::unique_ptr<ProxyService> proxy_service) {
     proxy_service_ = std::move(proxy_service);
   }
 
   // Call these functions to specify hard-coded Accept-Language
   // or User-Agent header values for all requests that don't
   // have the headers already set.
   void set_accept_language(const std::string& accept_language) {
     accept_language_ = accept_language;
   }
@@ skipping 168 matching lines @@
   // SdchOwner in net/sdch/sdch_owner.h is a simple policy object.
   void set_sdch_enabled(bool enable) { sdch_enabled_ = enable; }
 
   // Sets a specific HttpServerProperties for use in the
   // URLRequestContext rather than creating a default HttpServerPropertiesImpl.
   void SetHttpServerProperties(
       std::unique_ptr<HttpServerProperties> http_server_properties);
 
   std::unique_ptr<URLRequestContext> Build();
 
+ protected:
+  // Lets subclasses override ProxyService creation, using a ProxyService that
+  // uses the URLRequestContext itself to get PAC scripts. When this method is
+  // invoked, the URLRequestContext is not yet ready to service requests.
+  virtual std::unique_ptr<ProxyService> CreateProxyService(
+      std::unique_ptr<ProxyConfigService> proxy_config_service,
+      URLRequestContext* url_request_context,
+      HostResolver* host_resolver,
+      NetworkDelegate* network_delegate,
+      NetLog* net_log);
+
  private:
   const char* name_;
   bool enable_brotli_;
   NetworkQualityEstimator* network_quality_estimator_;
 
   std::string accept_language_;
   std::string user_agent_;
   // Include support for data:// requests.
   bool data_enabled_;
 #if !BUILDFLAG(DISABLE_FILE_SUPPORT)
@@ skipping 32 matching lines @@
   // Not owned by the context builder. Once it is set to a non-null value, it
   // is guaranteed to be non-null during the lifetime of |this|.
   SocketPerformanceWatcherFactory* socket_performance_watcher_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(URLRequestContextBuilder);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_CONTEXT_BUILDER_H_