Keep browser process alive while there are platform apps with background pages running.

chrome/browser/extensions/platform_app_service_factory.h

+// 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.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_PLATFORM_APP_SERVICE_FACTORY_H_
+#define CHROME_BROWSER_EXTENSIONS_PLATFORM_APP_SERVICE_FACTORY_H_
+
+#include "base/memory/singleton.h"
+#include "chrome/browser/extensions/platform_app_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/profiles/profile_keyed_service_factory.h"
+
+namespace extensions {
+
+class PlatformAppServiceFactory : public ProfileKeyedServiceFactory {

[Andrew T Wilson (Slow), 2012/11/28 10:16:24]

nit: (again, fine as-is) it's nice to document if the factory behavior differs
from the default (for example, if Incognito profiles have an instance of the
service, etc). Not a huge deal since callers can probably infer this from the
override below. But if GetForProfile() can sometimes return NULL, it's useful to
document under what circumstances it can do so (or likewise, if it never returns
NULL, that's good to document too).

+ public:
+  static PlatformAppService* GetForProfile(Profile* profile);
+
+  static PlatformAppServiceFactory* GetInstance();
+ private:
+  friend struct DefaultSingletonTraits<PlatformAppServiceFactory>;
+
+  PlatformAppServiceFactory();
+  virtual ~PlatformAppServiceFactory();
+
+  // ProfileKeyedServiceFactory
+  virtual ProfileKeyedService* BuildServiceInstanceFor(
+      Profile* profile) const OVERRIDE;
+  virtual bool ServiceHasOwnInstanceInIncognito() const OVERRIDE;
+  virtual bool ServiceIsCreatedWithProfile() const OVERRIDE;
+  virtual bool ServiceIsNULLWhileTesting() const OVERRIDE;
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_PLATFORM_APP_SERVICE_FACTORY_H_