Moved ExternalExtensionLoaders/Providers into extensions namespace

chrome/browser/extensions/external_extension_loader.h

-// Copyright (c) 2011 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_EXTERNAL_EXTENSION_LOADER_H_
-#define CHROME_BROWSER_EXTENSIONS_EXTERNAL_EXTENSION_LOADER_H_
-#pragma once
-
-#include "base/file_path.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
-
-class ExternalExtensionProviderImpl;
-
-namespace base {
-class DictionaryValue;
-}
-
-// Base class for gathering a list of external extensions. Subclasses
-// implement loading from registry, JSON file, policy.
-// Instances are owned by ExternalExtensionProviderImpl objects.
-// Instances are created on the UI thread and expect public method calls from
-// the UI thread. Some subclasses introduce new methods that are executed on the
-// FILE thread.
-// The sequence of loading the extension list:
-// 1.) StartLoading() - checks if a loading task is already running
-// 2.) Load() - implemented in subclasses
-// 3.) LoadFinished()
-// 4.) owner_->SetPrefs()
-class ExternalExtensionLoader
-    : public base::RefCountedThreadSafe<ExternalExtensionLoader> {
- public:
-  explicit ExternalExtensionLoader();
-
-  // Specifies the provider that owns this object.
-  void Init(ExternalExtensionProviderImpl* owner);
-
-  // Called by the owner before it gets deleted.
-  void OwnerShutdown();
-
-  // Initiates the possibly asynchronous loading of extension list.
-  // It is the responsibility of the caller to ensure that calls to
-  // this method do not overlap with each other.
-  // Implementations of this method should save the loaded results
-  // in prefs_ and then call LoadFinished.
-  virtual void StartLoading() = 0;
-
-  // Some external providers allow relative file paths to local CRX files.
-  // Subclasses that want this behavior should override this method to
-  // return the absolute path from which relative paths should be resolved.
-  // By default, return an empty path, which indicates that relative paths
-  // are not allowed.
-  virtual const FilePath GetBaseCrxFilePath();
-
- protected:
-  virtual ~ExternalExtensionLoader();
-
-  // Notifies the provider that the list of extensions has been loaded.
-  void LoadFinished();
-
-  // Used for passing the list of extensions from the method that loads them
-  // to |LoadFinished|. To ensure thread safety, the rules are the following:
-  // if this value is written on another thread than the UI, then it should
-  // only be written in a task that was posted from |StartLoading|. After that,
-  // this task should invoke |LoadFinished| with a PostTask. This scheme of
-  // posting tasks will avoid concurrent access and imply the necessary memory
-  // barriers.
-  scoped_ptr<base::DictionaryValue> prefs_;
-
- private:
-  friend class base::RefCountedThreadSafe<ExternalExtensionLoader>;
-
-  ExternalExtensionProviderImpl* owner_;  // weak
-
-  // Set to true if loading the extensions is already running. New requests
-  // are ignored while this is set true.
-  bool running_;
-
-  DISALLOW_COPY_AND_ASSIGN(ExternalExtensionLoader);
-};
-
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTERNAL_EXTENSION_LOADER_H_