Remove all the ephemeral apps code.

extensions/browser/extension_prefs.h

Index: extensions/browser/extension_prefs.h
diff --git a/extensions/browser/extension_prefs.h b/extensions/browser/extension_prefs.h
index b2a3dd6c2c31fa07cf0fa6427fa30b8b28900dd8..1236d4e65e90eee295231b9e412736013d741576 100644
--- a/extensions/browser/extension_prefs.h
+++ b/extensions/browser/extension_prefs.h
@@ -452,12 +452,6 @@ class ExtensionPrefs : public ExtensionScopedPrefs, public KeyedService {
   // information.
   scoped_ptr<ExtensionsInfo> GetAllDelayedInstallInfo() const;
 
-  // Returns true if the extension is an ephemeral app.
-  bool IsEphemeralApp(const std::string& extension_id) const;
-
-  // Promotes an ephemeral app to a regular installed app.
-  void OnEphemeralAppPromoted(const std::string& extension_id);
-
   // Returns true if the user repositioned the app on the app launcher via drag
   // and drop.
   bool WasAppDraggedByUser(const std::string& extension_id) const;