Make InstallObserver methods not pure-virtual

chrome/browser/ui/app_list/search/app_result.h

Index: chrome/browser/ui/app_list/search/app_result.h
diff --git a/chrome/browser/ui/app_list/search/app_result.h b/chrome/browser/ui/app_list/search/app_result.h
index 6872f9c7b8d312ca9e8091d76330248d556e7d61..061d17cca0f84d67d069620af92aac3a0a671633 100644
--- a/chrome/browser/ui/app_list/search/app_result.h
+++ b/chrome/browser/ui/app_list/search/app_result.h
@@ -73,22 +73,10 @@ class AppResult : public ChromeSearchResult,
   virtual void ExtensionEnableFlowAborted(bool user_initiated) OVERRIDE;
 
   // extensions::InstallObserver overrides:
-  virtual void OnBeginExtensionInstall(
-      const ExtensionInstallParams& params) OVERRIDE;
-  virtual void OnDownloadProgress(const std::string& extension_id,
-                                  int percent_downloaded) OVERRIDE;
-  virtual void OnInstallFailure(const std::string& extension_id) OVERRIDE;
-  virtual void OnExtensionInstalled(
-      const extensions::Extension* extension) OVERRIDE;
   virtual void OnExtensionLoaded(
       const extensions::Extension* extension) OVERRIDE;
-  virtual void OnExtensionUnloaded(
-      const extensions::Extension* extension) OVERRIDE;
   virtual void OnExtensionUninstalled(
       const extensions::Extension* extension) OVERRIDE;
-  virtual void OnAppsReordered() OVERRIDE;
-  virtual void OnAppInstalledToAppList(
-      const std::string& extension_id) OVERRIDE;
   virtual void OnShutdown() OVERRIDE;
 
   Profile* profile_;