Fix resource leak on extension window closing.

chrome/browser/chromeos/arc/arc_support_host.h

 // Copyright 2016 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 CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_
 
 #include "base/macros.h"
 #include "chrome/browser/chromeos/arc/arc_auth_service.h"
 #include "components/prefs/pref_change_registrar.h"
 #include "extensions/browser/api/messaging/native_message_host.h"
 #include "ui/display/display_observer.h"
 
 // Supports communication with Arc support dialog.
 class ArcSupportHost : public extensions::NativeMessageHost,
                        public arc::ArcAuthService::Observer,
                        public display::DisplayObserver {
  public:
   static const char kHostName[];
   static const char kHostAppId[];
   static const char kStorageId[];
   static const char* const kHostOrigin[];
 
   static std::unique_ptr<NativeMessageHost> Create();
 
   ~ArcSupportHost() override;
 
+  // Requests to close the extension window.
+  void Close();
+
   // Overrides NativeMessageHost:
   void Start(Client* client) override;
   void OnMessage(const std::string& request_string) override;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner() const override;
 
   // Overrides arc::ArcAuthService::Observer:
+  // TODO(hidehiko): Get rid of Observer interface.
   void OnOptInUIClose() override;
   void OnOptInUIShowPage(arc::ArcAuthService::UIPage page,
                          const base::string16& status) override;
 
   // display::DisplayObserver:
   void OnDisplayAdded(const display::Display& new_display) override;
   void OnDisplayRemoved(const display::Display& old_display) override;
   void OnDisplayMetricsChanged(const display::Display& display,
                                uint32_t changed_metrics) override;
 
  private:
   ArcSupportHost();
 
   bool Initialize();
   void OnMetricsPreferenceChanged();
   void OnBackupAndRestorePreferenceChanged();
   void OnLocationServicePreferenceChanged();
   void SendMetricsMode();
   void SendBackupAndRestoreMode();
   void SendLocationServicesMode();
   void SendOptionMode(const std::string& action_name,
                       const std::string& pref_name);
   void EnableMetrics(bool is_enabled);
   void EnableBackupRestore(bool is_enabled);
   void EnableLocationService(bool is_enabled);
 
   // Unowned pointer.
   Client* client_ = nullptr;
 
+  // Keep if Close() is requested from the browser.
+  // TODO(hidehiko): Remove this. This is temporarily introduced for checking
+  // if ArcAuthService::CancelAuthCode() needs to be invoked or not.
+  // ArcAuthService should know its own state and the transition so moving to
+  // there should simplify the structure. However, it is blocked by the current
+  // dependency. For the clean up, more refactoring is needed, which can be
+  // bigger changes.
+  bool close_requested_ = false;
+
   // Used to track metrics preference.
   PrefChangeRegistrar pref_local_change_registrar_;
   // Used to track backup&restore and location service preference.
   PrefChangeRegistrar pref_change_registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcSupportHost);
 };
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_SUPPORT_HOST_H_