Use EventRouter::Get instead of ExtensionSystem::Get(browser_context)->event_router()

chrome/browser/ui/webui/app_list/start_page_handler.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/ui/webui/app_list/start_page_handler.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
-#include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/omaha_query_params/omaha_query_params.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/hotword_service.h"
 #include "chrome/browser/ui/app_list/app_list_controller_delegate.h"
 #include "chrome/browser/ui/app_list/app_list_service.h"
 #include "chrome/browser/ui/app_list/recommended_apps.h"
 #include "chrome/browser/ui/app_list/start_page_service.h"
 #include "chrome/browser/ui/host_desktop.h"
 #include "chrome/browser/ui/webui/extensions/extension_icon_source.h"
 #include "chrome/common/pref_names.h"
-#include "content/public/browser/notification_details.h"
-#include "content/public/browser/notification_source.h"
 #include "content/public/browser/web_ui.h"
+#include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_icon_set.h"
 #include "ui/app_list/app_list_switches.h"
 #include "ui/app_list/speech_ui_model_observer.h"
 #include "ui/events/event_constants.h"
 
 namespace app_list {
 
 namespace {
@@ skipping 17 matching lines @@
       ExtensionIconSet::MATCH_BIGGER,
       grayscale,
       &icon_exists);
   dict->SetString("iconUrl", icon_url.spec());
 
   return dict.Pass();
 }
 
 }  // namespace
 
-StartPageHandler::StartPageHandler() : recommended_apps_(NULL) {}
+StartPageHandler::StartPageHandler()
+    : recommended_apps_(NULL), extension_registry_observer_(this) {
+}
 
 StartPageHandler::~StartPageHandler() {
   if (recommended_apps_)
     recommended_apps_->RemoveObserver(this);
 }
 
 void StartPageHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback(
       "initialize",
       base::Bind(&StartPageHandler::HandleInitialize, base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "launchApp",
       base::Bind(&StartPageHandler::HandleLaunchApp, base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "speechResult",
       base::Bind(&StartPageHandler::HandleSpeechResult,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "speechSoundLevel",
       base::Bind(&StartPageHandler::HandleSpeechSoundLevel,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "setSpeechRecognitionState",
       base::Bind(&StartPageHandler::HandleSpeechRecognition,
                  base::Unretained(this)));
 }
 
-void StartPageHandler::Observe(int type,
-                               const content::NotificationSource& source,
-                               const content::NotificationDetails& details) {
+void StartPageHandler::OnExtensionLoaded(
+    content::BrowserContext* browser_context,
+    const extensions::Extension* extension) {
 #if defined(OS_CHROMEOS)
   DCHECK_EQ(Profile::FromWebUI(web_ui()),
             content::Source<Profile>(source).ptr());

[Devlin, 2014/05/16 17:34:04]

This won't compile - the |source| variable is gone.
Instead:
DCHECK_EQ(Profile::FromWebUI(web_ui()),
          Profile::FromBrowserContext(browser_context));

-  switch (type) {
-    case chrome::NOTIFICATION_EXTENSION_LOADED_DEPRECATED: {
-      extensions::Extension* extension =
-          content::Details<extensions::Extension>(details).ptr();
-      if (extension->id() == extension_misc::kHotwordExtensionId)
-        OnHotwordEnabledChanged();
-      break;
-    }
-    case chrome::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED: {
-      extensions::UnloadedExtensionInfo* info =
-          content::Details<extensions::UnloadedExtensionInfo>(details).ptr();
-      if (info->extension->id() == extension_misc::kHotwordExtensionId)
-        OnHotwordEnabledChanged();
-      break;
-    }
-    default:
-      NOTREACHED();
-      break;
-  }
+  if (extension->id() == extension_misc::kHotwordExtensionId)
+    OnHotwordEnabledChanged();
 #endif
 }
 
+void StartPageHandler::OnExtensionUnloaded(
+    content::BrowserContext* browser_context,
+    const extensions::Extension* extension,
+    extensions::UnloadedExtensionInfo::Reason reason) {
+#if defined(OS_CHROMEOS)
+  DCHECK_EQ(Profile::FromWebUI(web_ui()),

[Devlin, 2014/05/16 17:34:04]

same as above.

+            content::Source<Profile>(source).ptr());
+  if (extension->id() == extension_misc::kHotwordExtensionId)
+    OnHotwordEnabledChanged();
+#endif
+}
+
 void StartPageHandler::OnRecommendedAppsChanged() {
   SendRecommendedApps();
 }
 
 void StartPageHandler::SendRecommendedApps() {
   const RecommendedApps::Apps& recommends = recommended_apps_->apps();
 
   base::ListValue recommended_list;
   for (size_t i = 0; i < recommends.size(); ++i) {
     recommended_list.Append(CreateAppInfo(recommends[i].get()).release());
   }
 
   web_ui()->CallJavascriptFunction("appList.startPage.setRecommendedApps",
                                    recommended_list);
 }
 
 #if defined(OS_CHROMEOS)
 void StartPageHandler::OnHotwordEnabledChanged() {
   // If the hotword extension is new enough, we should use the new
   // hotwordPrivate API to provide the feature.
   // TODO(mukai): remove this after everything gets stable.
   Profile* profile = Profile::FromWebUI(web_ui());
   ExtensionService* extension_service =
       extensions::ExtensionSystem::Get(profile)->extension_service();
   if (!extension_service)
     return;
 
   const extensions::Extension* hotword_extension =
       extension_service->GetExtensionById(

[Devlin, 2014/05/16 17:34:04]

Please change this to be ExtensionRegistry::GetExtensionById().  The fewer times
we can call into ExtensionService for stuff like this (especially after
notifications) the better.

           extension_misc::kHotwordExtensionId, false /* include_disabled */);
   if (hotword_extension && hotword_extension->version()->CompareTo(
           base::Version(kOldHotwordExtensionVersionString)) <= 0) {
     StartPageService* service = StartPageService::Get(profile);
     web_ui()->CallJavascriptFunction(
         "appList.startPage.setHotwordEnabled",
         base::FundamentalValue(service->HotwordEnabled()));
   }
 }
 #endif
@@ skipping 11 matching lines @@
 
 #if defined(OS_CHROMEOS)
   if (app_list::switches::IsVoiceSearchEnabled() &&
       HotwordService::DoesHotwordSupportLanguage(profile)) {
     OnHotwordEnabledChanged();
     pref_change_registrar_.Init(profile->GetPrefs());
     pref_change_registrar_.Add(
         prefs::kHotwordSearchEnabled,
         base::Bind(&StartPageHandler::OnHotwordEnabledChanged,
                    base::Unretained(this)));
-    registrar_.Add(this,
-                   chrome::NOTIFICATION_EXTENSION_LOADED_DEPRECATED,
-                   content::Source<Profile>(profile));
-    registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED,
-                   content::Source<Profile>(profile));
+
+    extension_registry_observer_.Add(
+        extensions::ExtensionRegistry::Get(profile));
   }
 #endif
 
   web_ui()->CallJavascriptFunction(
       "appList.startPage.setNaclArch",
       base::StringValue(chrome::OmahaQueryParams::GetNaclArch()));
 
   if (!app_list::switches::IsExperimentalAppListEnabled()) {
     web_ui()->CallJavascriptFunction(
         "appList.startPage.onAppListShown",
@@ skipping 60 matching lines @@
   else if (state_string == "STOPPING")
     new_state = SPEECH_RECOGNITION_STOPPING;
 
   StartPageService* service =
       StartPageService::Get(Profile::FromWebUI(web_ui()));
   if (service)
     service->OnSpeechRecognitionStateChanged(new_state);
 }
 
 }  // namespace app_list