Turn on component updater on chromeos, only for the pnacl component.

chrome/browser/browser_process_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.
 
 // When each service is created, we set a flag indicating this. At this point,
 // the service initialization could fail or succeed. This allows us to remember
 // if we tried to create a service, and not try creating it over and over if
 // the creation failed.
 
 #ifndef CHROME_BROWSER_BROWSER_PROCESS_IMPL_H_
@@ skipping 114 matching lines @@
       safe_browsing_detection_service() OVERRIDE;
 
 #if (defined(OS_WIN) || defined(OS_LINUX)) && !defined(OS_CHROMEOS)
   virtual void StartAutoupdateTimer() OVERRIDE;
 #endif
 
   virtual ChromeNetLog* net_log() OVERRIDE;
   virtual prerender::PrerenderTracker* prerender_tracker() OVERRIDE;
   virtual ComponentUpdateService* component_updater() OVERRIDE;
   virtual CRLSetFetcher* crl_set_fetcher() OVERRIDE;
+  virtual PnaclComponentInstaller* pnacl_component_installer() OVERRIDE;
   virtual BookmarkPromptController* bookmark_prompt_controller() OVERRIDE;
   virtual chrome::MediaFileSystemRegistry*
       media_file_system_registry() OVERRIDE;
   virtual void PlatformSpecificCommandLineProcessing(
       const CommandLine& command_line) OVERRIDE;
   virtual bool created_local_state() const OVERRIDE;
 
   static void RegisterPrefs(PrefRegistrySimple* registry);
 
  private:
@@ skipping 134 matching lines @@
 
   // Gets called by autoupdate timer to see if browser needs restart and can be
   // restarted, and if that's the case, restarts the browser.
   void OnAutoupdateTimer();
   bool CanAutorestartForUpdate() const;
   void RestartBackgroundInstance();
 #endif  // defined(OS_WIN) || defined(OS_LINUX) && !defined(OS_CHROMEOS)
 
 #if defined(OS_CHROMEOS)
   scoped_ptr<chromeos::OomPriorityManager> oom_priority_manager_;
-#else
+#endif
+  // component updater is normally not used under ChromeOS due
+  // to concerns over integrity of data shared between profiles,
+  // but some users of component updater only install per-user.
   scoped_ptr<ComponentUpdateService> component_updater_;
-
   scoped_refptr<CRLSetFetcher> crl_set_fetcher_;
-#endif
+  scoped_ptr<PnaclComponentInstaller> pnacl_component_installer_;
 
 #if defined(ENABLE_PLUGIN_INSTALLATION)
   scoped_refptr<PluginsResourceService> plugins_resource_service_;
 #endif
 
 #if defined(OS_WIN) && defined(USE_AURA)
   void PerformInitForWindowsAura(const CommandLine& command_line);
 
   // Hosts the channel for the Windows 8 metro viewer process which runs in
   // the ASH environment.
   scoped_ptr<MetroViewerProcessHost> metro_viewer_process_host_;
 #endif
 
 #if defined(OS_MACOSX)
   // Hosts the IPC channel factory that App Shims connect to on Mac.
   scoped_ptr<AppShimHostManager> app_shim_host_manager_;
 #endif
 
   // TODO(eroman): Remove this when done debugging 113031. This tracks
   // the callstack which released the final module reference count.
   base::debug::StackTrace release_last_reference_callstack_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserProcessImpl);
 };
 
 #endif  // CHROME_BROWSER_BROWSER_PROCESS_IMPL_H_