Cleanup/ Remove deprecated extension notification from ExtensionHost

Remove deprecated extension notification from ExtensionHost.
Use ExtensionRegistryObserver instead.

BUG=411568

Review URL: https://codereview.chromium.org/964193002

Cr-Commit-Position: refs/heads/master@{#318803}

chrome/browser/extensions/extension_view_host.cc

@@ -107,9 +107,9 @@ void ExtensionViewHost::LoadInitialURL() {
   if (!ExtensionSystem::Get(browser_context())->
           runtime_data()->IsBackgroundPageReady(extension())) {
     // Make sure the background page loads before any others.
-    registrar()->Add(this,
-                     extensions::NOTIFICATION_EXTENSION_BACKGROUND_PAGE_READY,
-                     content::Source<Extension>(extension()));
+    registrar_.Add(this,
+                   extensions::NOTIFICATION_EXTENSION_BACKGROUND_PAGE_READY,
+                   content::Source<Extension>(extension()));
     return;
   }
 
@@ -296,13 +296,11 @@ WebContents* ExtensionViewHost::GetVisibleWebContents() const {
 void ExtensionViewHost::Observe(int type,
                                 const content::NotificationSource& source,
                                 const content::NotificationDetails& details) {
-  if (type == extensions::NOTIFICATION_EXTENSION_BACKGROUND_PAGE_READY) {
-    DCHECK(ExtensionSystem::Get(browser_context())->
-               runtime_data()->IsBackgroundPageReady(extension()));
-    LoadInitialURL();
-    return;
-  }
-  ExtensionHost::Observe(type, source, details);
+  DCHECK_EQ(type, extensions::NOTIFICATION_EXTENSION_BACKGROUND_PAGE_READY);
+  DCHECK(ExtensionSystem::Get(browser_context())
+             ->runtime_data()
+             ->IsBackgroundPageReady(extension()));
+  LoadInitialURL();
 }
 
 }  // namespace extensions

chrome/browser/extensions/extension_view_host.h

@@ -9,6 +9,8 @@
 #include "components/web_modal/popup_manager.h"
 #include "components/web_modal/web_contents_modal_dialog_host.h"
 #include "components/web_modal/web_contents_modal_dialog_manager_delegate.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
 #include "extensions/browser/extension_host.h"
 
 class Browser;
@@ -29,7 +31,8 @@ class ExtensionView;
 class ExtensionViewHost
     : public ExtensionHost,
       public web_modal::WebContentsModalDialogManagerDelegate,
-      public web_modal::WebContentsModalDialogHost {
+      public web_modal::WebContentsModalDialogHost,
+      public content::NotificationObserver {
  public:
   ExtensionViewHost(const Extension* extension,
                     content::SiteInstance* site_instance,
@@ -127,6 +130,8 @@ class ExtensionViewHost
   // a parent window.
   scoped_ptr<web_modal::PopupManager> popup_manager_;
 
+  content::NotificationRegistrar registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionViewHost);
 };
 

extensions/browser/extension_host.cc

@@ -13,8 +13,6 @@
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/native_web_keyboard_event.h"
 #include "content/public/browser/notification_service.h"
-#include "content/public/browser/notification_source.h"
-#include "content/public/browser/notification_types.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host_view.h"
@@ -25,6 +23,7 @@
 #include "extensions/browser/extension_host_delegate.h"
 #include "extensions/browser/extension_host_observer.h"
 #include "extensions/browser/extension_host_queue.h"
+#include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/browser/load_monitoring_extension_host_queue.h"
@@ -77,15 +76,15 @@ ExtensionHost::ExtensionHost(const Extension* extension,
 
   // Listen for when an extension is unloaded from the same profile, as it may
   // be the same extension that this points to.
-  registrar_.Add(this,
-                 extensions::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED,
-                 content::Source<BrowserContext>(browser_context_));
+  ExtensionRegistry::Get(browser_context_)->AddObserver(this);
 
   // Set up web contents observers and pref observers.
   delegate_->OnExtensionHostCreated(host_contents());
 }
 
 ExtensionHost::~ExtensionHost() {
+  ExtensionRegistry::Get(browser_context_)->RemoveObserver(this);
+
   if (extension_host_type_ == VIEW_TYPE_EXTENSION_BACKGROUND_PAGE &&
       extension_ && BackgroundInfo::HasLazyBackgroundPage(extension_) &&
       load_start_.get()) {
@@ -210,23 +209,15 @@ bool ExtensionHost::IsBackgroundPage() const {
   return true;
 }
 
-void ExtensionHost::Observe(int type,
-                            const content::NotificationSource& source,
-                            const content::NotificationDetails& details) {
-  switch (type) {
-    case extensions::NOTIFICATION_EXTENSION_UNLOADED_DEPRECATED:
-      // The extension object will be deleted after this notification has been
-      // sent. Null it out so that dirty pointer issues don't arise in cases
-      // when multiple ExtensionHost objects pointing to the same Extension are
-      // present.
-      if (extension_ == content::Details<UnloadedExtensionInfo>(details)->
-          extension) {
-        extension_ = nullptr;
-      }
-      break;
-    default:
-      NOTREACHED() << "Unexpected notification sent.";
-      break;
+void ExtensionHost::OnExtensionUnloaded(
+    content::BrowserContext* browser_context,
+    const Extension* extension,
+    UnloadedExtensionInfo::Reason reason) {
+  // The extension object will be deleted after this notification has been sent.
+  // Null it out so that dirty pointer issues don't arise in cases when multiple
+  // ExtensionHost objects pointing to the same Extension are present.
+  if (extension_ == extension) {
+    extension_ = nullptr;
   }
 }
 

extensions/browser/extension_host.h

@@ -7,18 +7,16 @@
 
 #include <set>
 #include <string>
-#include <vector>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "base/timer/elapsed_timer.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "extensions/browser/deferred_start_render_host.h"
 #include "extensions/browser/extension_function_dispatcher.h"
+#include "extensions/browser/extension_registry_observer.h"
 #include "extensions/common/stack_frame.h"
 #include "extensions/common/view_type.h"
 
@@ -49,7 +47,7 @@ class ExtensionHost : public DeferredStartRenderHost,
                       public content::WebContentsDelegate,
                       public content::WebContentsObserver,
                       public ExtensionFunctionDispatcher::Delegate,
-                      public content::NotificationObserver {
+                      public ExtensionRegistryObserver {
  public:
   ExtensionHost(const Extension* extension,
                 content::SiteInstance* site_instance,
@@ -127,14 +125,12 @@ class ExtensionHost : public DeferredStartRenderHost,
                                   content::MediaStreamType type) override;
   bool IsNeverVisible(content::WebContents* web_contents) override;
 
-  // content::NotificationObserver:
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
+  // ExtensionRegistryObserver:
+  void OnExtensionUnloaded(content::BrowserContext* browser_context,
+                           const Extension* extension,
+                           UnloadedExtensionInfo::Reason reason) override;
 
  protected:
-  content::NotificationRegistrar* registrar() { return &registrar_; }
-
   // Called after the extension page finishes loading but before the
   // EXTENSION_HOST_DID_STOP_LOADING notification is sent.
   virtual void OnDidStopLoading();
@@ -191,8 +187,6 @@ class ExtensionHost : public DeferredStartRenderHost,
   // Messages sent out to the renderer that have not been acknowledged yet.
   std::set<int> unacked_messages_;
 
-  content::NotificationRegistrar registrar_;
-
   ExtensionFunctionDispatcher extension_function_dispatcher_;
 
   // The type of view being hosted.