Remove InstallTracker's extension installed, uninstalled observers.

chrome/browser/ui/app_list/search/webstore/webstore_result.cc

Index: chrome/browser/ui/app_list/search/webstore/webstore_result.cc
diff --git a/chrome/browser/ui/app_list/search/webstore/webstore_result.cc b/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
index aff9226b57c4905164c7fceedf1440f6704f96af..cc5e8dee9b9bb9057b065ed6ae8856a9f31f8ef1 100644
--- a/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
+++ b/chrome/browser/ui/app_list/search/webstore/webstore_result.cc
@@ -21,6 +21,7 @@
 #include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/common/chrome_switches.h"
+#include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/browser/extension_util.h"
 #include "extensions/common/extension.h"
@@ -75,7 +76,8 @@ WebstoreResult::WebstoreResult(Profile* profile,
       icon_url_(icon_url),
       weak_factory_(this),
       controller_(controller),
-      install_tracker_(NULL) {
+      install_tracker_(NULL),
+      extension_registry_(NULL) {
   set_id(extensions::Extension::GetBaseURLFromExtensionId(app_id_).spec());
   set_relevance(0.0);  // What is the right value to use?
 
@@ -94,11 +96,12 @@ WebstoreResult::WebstoreResult(Profile* profile,
       gfx::Size(kIconSize, kIconSize));
   SetIcon(icon_);
 
-  StartObservingInstall();
+  StartObserving();
 }
 
 WebstoreResult::~WebstoreResult() {
   StopObservingInstall();
+  StopObservingRegistry();
 }
 
 void WebstoreResult::Open(int event_flags) {
@@ -210,20 +213,28 @@ void WebstoreResult::InstallCallback(bool success, const std::string& error) {
   SetPercentDownloaded(100);
 }
 
-void WebstoreResult::StartObservingInstall() {
-  DCHECK(!install_tracker_);
+void WebstoreResult::StartObserving() {
+  DCHECK(!install_tracker_ && !extension_registry_);
 
   install_tracker_ = extensions::InstallTrackerFactory::GetForProfile(profile_);
   install_tracker_->AddObserver(this);
+
+  extension_registry_ = extensions::ExtensionRegistry::Get(profile_);
+  extension_registry_->AddObserver(this);
 }
 
 void WebstoreResult::StopObservingInstall() {
   if (install_tracker_)
     install_tracker_->RemoveObserver(this);
-
   install_tracker_ = NULL;
 }
 
+void WebstoreResult::StopObservingRegistry() {
+  if (extension_registry_)
+    extension_registry_->RemoveObserver(this);
+  extension_registry_ = NULL;
+}
+
 void WebstoreResult::OnDownloadProgress(const std::string& extension_id,
                                         int percent_downloaded) {
   if (extension_id != app_id_ || percent_downloaded < 0)
@@ -232,8 +243,12 @@ void WebstoreResult::OnDownloadProgress(const std::string& extension_id,
   SetPercentDownloaded(percent_downloaded);
 }
 
-void WebstoreResult::OnExtensionInstalled(
-    const extensions::Extension* extension) {
+void WebstoreResult::OnExtensionWillBeInstalled(
+    content::BrowserContext* browser_context,
+    const extensions::Extension* extension,
+    bool is_update,
+    bool from_ephemeral,
+    const std::string& old_name) {
   if (extension->id() != app_id_)
     return;
 
@@ -246,6 +261,10 @@ void WebstoreResult::OnShutdown() {
   StopObservingInstall();
 }
 
+void WebstoreResult::OnShutdown(extensions::ExtensionRegistry* registry) {
+  StopObservingRegistry();
+}
+
 ChromeSearchResultType WebstoreResult::GetType() {
   return SEARCH_WEBSTORE_SEARCH_RESULT;
 }