Extract ProcessManager from ExtensionSystem.

extensions/browser/process_manager_factory.h

+// Copyright 2014 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 EXTENSIONS_BROWSER_PROCESS_MANAGER_FACTORY_H_
+#define EXTENSIONS_BROWSER_PROCESS_MANAGER_FACTORY_H_
+
+#include "base/memory/singleton.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+namespace extensions {
+
+class ProcessManager;
+
+class ProcessManagerFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  static ProcessManager* GetForBrowserContext(content::BrowserContext* context);
+  // Returns NULL if there is no ProcessManager associated with this context.
+  static ProcessManager* GetForBrowserContextIfExists(
+      content::BrowserContext* context);
+  static ProcessManagerFactory* GetInstance();
+
+ private:
+  friend struct DefaultSingletonTraits<ProcessManagerFactory>;
+
+  ProcessManagerFactory();
+  virtual ~ProcessManagerFactory();
+
+  // BrowserContextKeyedServiceFactory
+  virtual KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  virtual content::BrowserContext* GetBrowserContextToUse(
+      content::BrowserContext* context) const override;
+
+  DISALLOW_COPY_AND_ASSIGN(ProcessManagerFactory);
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_PROCESS_MANAGER_FACTORY_H_