Revert of Remove ExtensionService Garbage-Collecting methods.

chrome/browser/extensions/extension_garbage_collector.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 CHROME_BROWSER_EXTENSIONS_EXTENSION_GARBAGE_COLLECTOR_H_
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_GARBAGE_COLLECTOR_H_
-
-#include <map>
-#include <string>
-
-#include "base/files/file_path.h"
-#include "base/memory/weak_ptr.h"
-
-namespace content {
-class BrowserContext;
-}
-
-class ExtensionService;
-
-namespace extensions {
-
-// The class responsible for cleaning up the cruft left behind on the file
-// system by uninstalled (or failed install) extensions.
-// The class is owned by ExtensionService, but is mostly independent. Tasks to
-// garbage collect extensions and isolated storage are posted once the
-// ExtensionSystem signals ready.
-class ExtensionGarbageCollector {
- public:
-  explicit ExtensionGarbageCollector(ExtensionService* extension_service);
-  ~ExtensionGarbageCollector();
-
-#if defined(OS_CHROMEOS)
-  // Enable or disable garbage collection. See |disable_garbage_collection_|.
-  void disable_garbage_collection() { disable_garbage_collection_ = true; }
-  void enable_garbage_collection() { disable_garbage_collection_ = false; }
-#endif
-
-  // Manually trigger GarbageCollectExtensions() for testing.
-  void GarbageCollectExtensionsForTest();
-
- private:
-  // Cleans up the extension install directory. It can end up with garbage in it
-  // if extensions can't initially be removed when they are uninstalled (eg if a
-  // file is in use).
-  // Obsolete version directories are removed, as are directories that aren't
-  // found in the ExtensionPrefs.
-  // The "Temp" directory that is used during extension installation will get
-  // removed iff there are no pending installations.
-  void GarbageCollectExtensions();
-
-  // The FILE-thread implementation of GarbageCollectExtensions().
-  void GarbageCollectExtensionsOnFileThread(
-      const std::multimap<std::string, base::FilePath>& extension_paths,
-      bool clean_temp_dir);
-
-  // Garbage collects apps/extensions isolated storage, if it is not currently
-  // active (i.e. is not in ExtensionRegistry::ENABLED). There is an exception
-  // for ephemeral apps, because they can outlive their cache lifetimes.
-  void GarbageCollectIsolatedStorageIfNeeded();
-
-  // The ExtensionService which owns this GarbageCollector.
-  ExtensionService* extension_service_;
-
-  // The BrowserContext associated with the GarbageCollector, for convenience.
-  // (This is equivalent to extension_service_->GetBrowserContext().)
-  content::BrowserContext* context_;
-
-  // The root extensions installation directory.
-  base::FilePath install_directory_;
-
-#if defined(OS_CHROMEOS)
-  // TODO(rkc): HACK alert - this is only in place to allow the
-  // kiosk_mode_screensaver to prevent its extension from getting garbage
-  // collected. Remove this once KioskModeScreensaver is removed.
-  // See crbug.com/280363
-  bool disable_garbage_collection_;
-#endif
-
-  // Generate weak pointers for safely posting to the file thread for garbage
-  // collection.
-  base::WeakPtrFactory<ExtensionGarbageCollector> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(ExtensionGarbageCollector);
-};
-
-}  // namespace extensions
-
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_GARBAGE_COLLECTOR_H_