Banish boilerplate. Profile-keyed API factory for extension API classes.

chrome/browser/extensions/api/tabs/tabs_windows_api.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/extensions/api/tabs/tabs_windows_api.h"
 
-#include "chrome/browser/extensions/api/tabs/tabs_windows_api_factory.h"
+#include "base/lazy_instance.h"
 #include "chrome/browser/extensions/api/tabs/windows_event_router.h"
 #include "chrome/browser/extensions/event_names.h"
 #include "chrome/browser/extensions/event_router.h"
 #include "chrome/browser/extensions/extension_system.h"
 
 namespace extensions {
 
 TabsWindowsAPI::TabsWindowsAPI(Profile* profile)
     : profile_(profile) {
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
       this, event_names::kOnWindowCreated);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
       this, event_names::kOnWindowRemoved);
   ExtensionSystem::Get(profile_)->event_router()->RegisterObserver(
       this, event_names::kOnWindowFocusedChanged);
 }
 
 TabsWindowsAPI::~TabsWindowsAPI() {
 }
 
 // static
 TabsWindowsAPI* TabsWindowsAPI::Get(Profile* profile) {
-  return TabsWindowsAPIFactory::GetForProfile(profile);
+  return ProfileKeyedAPIFactory<TabsWindowsAPI>::GetForProfile(profile);
 }
 
 WindowsEventRouter* TabsWindowsAPI::windows_event_router() {
   if (!windows_event_router_)
     windows_event_router_.reset(new WindowsEventRouter(profile_));
   return windows_event_router_.get();
 }
 
 void TabsWindowsAPI::Shutdown() {
   ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
 }
 
 void TabsWindowsAPI::OnListenerAdded(
     const extensions::EventListenerInfo& details) {
   windows_event_router();
   ExtensionSystem::Get(profile_)->event_router()->UnregisterObserver(this);
 }
 
+static base::LazyInstance<ProfileKeyedAPIFactory<TabsWindowsAPI> >
+g_factory = LAZY_INSTANCE_INITIALIZER;
+
+template <>
+ProfileKeyedAPIFactory<TabsWindowsAPI>*
+ProfileKeyedAPIFactory<TabsWindowsAPI>::GetInstance() {
+  return &g_factory.Get();
+}
+
 }  // namespace extensions