Shut down proxy resolver utility processes when no longer needed.

net/proxy/proxy_resolver_mojo.h

 // Copyright 2015 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_PROXY_PROXY_RESOLVER_MOJO_H_
 #define NET_PROXY_PROXY_RESOLVER_MOJO_H_
 
 #include <set>
 
+#include "base/callback_helpers.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "net/base/completion_callback.h"
 #include "net/base/load_states.h"
 #include "net/interfaces/host_resolver_service.mojom.h"
 #include "net/interfaces/proxy_resolver_service.mojom.h"
 #include "net/proxy/proxy_resolver.h"
 #include "net/proxy/proxy_resolver_script_data.h"
 #include "third_party/mojo/src/mojo/public/cpp/bindings/binding.h"
 
 class GURL;
 
 namespace net {
 
 class BoundNetLog;
 class HostResolver;
 class ProxyInfo;
 class MojoProxyResolverFactory;
 
 // Implementation of ProxyResolver that connects to a Mojo service to evaluate
 // PAC scripts. This implementation only knows about Mojo services, and
 // therefore that service may live in or out of process.
 //
-// This implementation handles disconnections from the Mojo service (i.e. if the
-// service is out-of-process and that process crashes) and transparently
-// re-connects to a new service.
+// This implementation reports disconnections from the Mojo service (i.e. if the
+// service is out-of-process and that process crashes) using the error code
+// ERR_PAC_SCRIPT_TERMINATED.
 class ProxyResolverMojo : public ProxyResolver, public mojo::ErrorHandler {
  public:
-  // Constructs a ProxyResolverMojo and connects to a new Mojo proxy resolver
-  // service using |mojo_proxy_resolver_factory|. The new Mojo proxy resolver
-  // uses |host_resolver| as the DNS resolver.  |mojo_proxy_resolver_factory|
-  // and |host_resolver| are not owned and must outlive this.
+  // Constructs a ProxyResolverMojo connected to a Mojo proxy resolver service
+  // using |mojo_proxy_resolver| that will delete |runner| when it is deleted.

[eroman, 2015/04/15 00:46:44]

this comment is hard to parse

[Sam McNally, 2015/04/15 06:04:22]

How about now?

   // TODO(amistry): Add ProxyResolverErrorObserver and NetLog.
-  ProxyResolverMojo(MojoProxyResolverFactory* mojo_proxy_resolver_factory,
-                    HostResolver* host_resolver);
+  ProxyResolverMojo(interfaces::ProxyResolverPtr mojo_proxy_resolver,
+                    scoped_ptr<base::ScopedClosureRunner> runner);
   ~ProxyResolverMojo() override;
 
   // ProxyResolver implementation:
   int GetProxyForURL(const GURL& url,
                      ProxyInfo* results,
                      const net::CompletionCallback& callback,
                      RequestHandle* request,
                      const BoundNetLog& net_log) override;
   void CancelRequest(RequestHandle request) override;
   LoadState GetLoadState(RequestHandle request) const override;
   void CancelSetPacScript() override;
   int SetPacScript(const scoped_refptr<ProxyResolverScriptData>& pac_script,
                    const net::CompletionCallback& callback) override;
 
  private:
   class Job;
 
   // Overridden from mojo::ErrorHandler:
   void OnConnectionError() override;
 
   // Callback for ProxyResolverService::SetPacScript.
   void OnSetPacScriptDone(
       const scoped_refptr<ProxyResolverScriptData>& pac_script,
       const net::CompletionCallback& callback,
       int32_t result);
 
-  void SetUpServices();
-
   void AbortPendingRequests();
 
   void RemoveJob(Job* job);
 
   // Connection to the Mojo proxy resolver.
   interfaces::ProxyResolverPtr mojo_proxy_resolver_ptr_;
 
-  // Mojo host resolver service and binding.
-  scoped_ptr<interfaces::HostResolver> mojo_host_resolver_;
-  scoped_ptr<mojo::Binding<interfaces::HostResolver>>
-      mojo_host_resolver_binding_;
-
-  // Factory for connecting to new Mojo proxy resolvers.
-  // Not owned.
-  MojoProxyResolverFactory* mojo_proxy_resolver_factory_;
-
-  // DNS resolver, saved for creating a new Mojo proxy resolver when the
-  // existing one disconnects (i.e. when utility process crashes).
-  HostResolver* host_resolver_;
-
   std::set<Job*> pending_jobs_;
   net::CancelableCompletionCallback set_pac_script_callback_;
 
   base::ThreadChecker thread_checker_;
 
+  scoped_ptr<base::ScopedClosureRunner> runner_;
+
   base::WeakPtrFactory<ProxyResolverMojo> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyResolverMojo);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_PROXY_RESOLVER_MOJO_H_