Revert of Make extensions DSE persistent in browser prefs

chrome/browser/extensions/api/settings_overrides/settings_overrides_api.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_SETTINGS_OVERRIDES_SETTINGS_OVERRIDES_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_SETTINGS_OVERRIDES_SETTINGS_OVERRIDES_API_H_
 
-#include <memory>
 #include <set>
 #include <string>
 
 #include "base/macros.h"
 #include "base/scoped_observer.h"
 #include "components/search_engines/template_url_service.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
 #include "extensions/browser/extension_registry_observer.h"
 
 class Profile;
 
 namespace extensions {
 class ExtensionRegistry;
 
 class SettingsOverridesAPI : public BrowserContextKeyedAPI,
                              public ExtensionRegistryObserver {
  public:
   explicit SettingsOverridesAPI(content::BrowserContext* context);
   ~SettingsOverridesAPI() override;
 
   // BrowserContextKeyedAPI implementation.
   static BrowserContextKeyedAPIFactory<SettingsOverridesAPI>*
       GetFactoryInstance();
 
  private:
   friend class BrowserContextKeyedAPIFactory<SettingsOverridesAPI>;
 
+  typedef std::set<scoped_refptr<const Extension> > PendingExtensions;
+
   // Wrappers around PreferenceAPI.
   void SetPref(const std::string& extension_id,
                const std::string& pref_key,
-               std::unique_ptr<base::Value> value) const;
+               base::Value* value);
   void UnsetPref(const std::string& extension_id,
-                 const std::string& pref_key) const;
+                 const std::string& pref_key);
 
   // ExtensionRegistryObserver implementation.
   void OnExtensionLoaded(content::BrowserContext* browser_context,
                          const Extension* extension) override;
   void OnExtensionUnloaded(content::BrowserContext* browser_context,
                            const Extension* extension,
                            UnloadedExtensionInfo::Reason reason) override;
 
+  // KeyedService implementation.
+  void Shutdown() override;
+
+  void OnTemplateURLsLoaded();
+
   void RegisterSearchProvider(const Extension* extension) const;
   // BrowserContextKeyedAPI implementation.
   static const char* service_name() { return "SettingsOverridesAPI"; }
 
   Profile* profile_;
   TemplateURLService* url_service_;
 
+  // List of extensions waiting for the TemplateURLService to Load to
+  // have search provider registered.
+  PendingExtensions pending_extensions_;
+
   // Listen to extension load, unloaded notifications.
   ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
       extension_registry_observer_;
 
+  std::unique_ptr<TemplateURLService::Subscription> template_url_sub_;
+
   DISALLOW_COPY_AND_ASSIGN(SettingsOverridesAPI);
 };
 
 template <>
 void BrowserContextKeyedAPIFactory<
     SettingsOverridesAPI>::DeclareFactoryDependencies();
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_SETTINGS_OVERRIDES_SETTINGS_OVERRIDES_API_H_