NetworkService: Destroy NetworkContexts on NetworkService teardown.

content/network/network_service.h

 // Copyright 2017 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 CONTENT_NETWORK_NETWORK_SERVICE_H_
 #define CONTENT_NETWORK_NETWORK_SERVICE_H_
 
 #include <memory>
 
 #include "base/macros.h"
+#include "content/common/content_export.h"
 #include "content/common/network_service.mojom.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "services/service_manager/public/cpp/service.h"
 
 namespace content {
 
+class NetworkContext;
+
 class NetworkService : public service_manager::Service,
                        public mojom::NetworkService {
  public:
   explicit NetworkService(
       std::unique_ptr<service_manager::BinderRegistry> registry);
   ~NetworkService() override;
 
+  CONTENT_EXPORT static std::unique_ptr<NetworkService> CreateForTesting();
+
+  // These are called by NetworkContexts as they are being created and
+  // destroyed.
+  void RegisterNetworkContext(NetworkContext* network_context);
+  void DeregisterNetworkContext(NetworkContext* network_context);
+
+  // mojom::NetworkService implementation:
+  void CreateNetworkContext(mojom::NetworkContextRequest request,
+                            mojom::NetworkContextParamsPtr params) override;
+
  private:
   class MojoNetLog;
 
+  // Used for tests.
+  NetworkService();
+
   // service_manager::Service implementation.
   void OnBindInterface(const service_manager::BindSourceInfo& source_info,
                        const std::string& interface_name,
                        mojo::ScopedMessagePipeHandle interface_pipe) override;
 
   void Create(const service_manager::BindSourceInfo& source_info,
               mojom::NetworkServiceRequest request);
 
-  // mojom::NetworkService implementation:
-  void CreateNetworkContext(mojom::NetworkContextRequest request,
-                            mojom::NetworkContextParamsPtr params) override;
-
   std::unique_ptr<MojoNetLog> net_log_;
 
   std::unique_ptr<service_manager::BinderRegistry> registry_;
 
   mojo::Binding<mojom::NetworkService> binding_;
 
+  // NetworkContexts register themselves with the NetworkService so that they
+  // can be cleaned up when the NetworkService goes away. This is needed as
+  // NetworkContexts share global state with the NetworkService, so must be
+  // destroyed first.
+  std::set<NetworkContext*> network_contexts_;
+
   DISALLOW_COPY_AND_ASSIGN(NetworkService);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_NETWORK_NETWORK_SERVICE_H_