Remove InstallTracker's extension load, unload observer

chrome/browser/extensions/install_observer.h

Index: chrome/browser/extensions/install_observer.h
diff --git a/chrome/browser/extensions/install_observer.h b/chrome/browser/extensions/install_observer.h
index 990a62eb36824420330a4f6bf067d609c0484cf1..fb11ae0cce0ff5e36fdebb41bcac6655a90b8672 100644
--- a/chrome/browser/extensions/install_observer.h
+++ b/chrome/browser/extensions/install_observer.h
@@ -62,11 +62,9 @@ class InstallObserver {
   // Called if the installation succeeds.
   virtual void OnExtensionInstalled(const Extension* extension) {}
 
-  // Called when an extension is [Loaded, Unloaded, Uninstalled] or an app is
+  // Called when an extension is [Uninstalled] or an app is
   // installed to the app list. These are simply forwarded from the
   // chrome::NOTIFICATIONs.
-  virtual void OnExtensionLoaded(const Extension* extension) {}
-  virtual void OnExtensionUnloaded(const Extension* extension) {}
   virtual void OnExtensionUninstalled(const Extension* extension) {}
   virtual void OnDisabledExtensionUpdated(const Extension* extension) {}
   virtual void OnAppInstalledToAppList(const std::string& extension_id) {}