Move Files.app files to ui/file_manager

chrome/browser/resources/file_manager/background/js/background.js

Index: chrome/browser/resources/file_manager/background/js/background.js
diff --git a/chrome/browser/resources/file_manager/background/js/background.js b/chrome/browser/resources/file_manager/background/js/background.js
deleted file mode 100644
index 8a12975ca011d2cb054bc5fe8521da9197efe000..0000000000000000000000000000000000000000
--- a/chrome/browser/resources/file_manager/background/js/background.js
+++ /dev/null
@@ -1,923 +0,0 @@
-// 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.
-
-'use strict';
-
-/**
- * Type of a Files.app's instance launch.
- * @enum {number}
- */
-var LaunchType = Object.freeze({
-  ALWAYS_CREATE: 0,
-  FOCUS_ANY_OR_CREATE: 1,
-  FOCUS_SAME_OR_CREATE: 2
-});
-
-/**
- * Root class of the background page.
- * @constructor
- */
-function Background() {
-  /**
-   * Map of all currently open app windows. The key is an app id.
-   * @type {Object.<string, AppWindow>}
-   */
-  this.appWindows = {};
-
-  /**
-   * Synchronous queue for asynchronous calls.
-   * @type {AsyncUtil.Queue}
-   */
-  this.queue = new AsyncUtil.Queue();
-
-  /**
-   * Progress center of the background page.
-   * @type {ProgressCenter}
-   */
-  this.progressCenter = new ProgressCenter();
-
-  /**
-   * File operation manager.
-   * @type {FileOperationManager}
-   */
-  this.fileOperationManager = new FileOperationManager();
-
-  /**
-   * Event handler for progress center.
-   * @type {FileOperationHandler}
-   * @private
-   */
-  this.fileOperationHandler_ = new FileOperationHandler(this);
-
-  /**
-   * Event handler for C++ sides notifications.
-   * @type {DeviceHandler}
-   * @private
-   */
-  this.deviceHandler_ = new DeviceHandler();
-
-  /**
-   * Drive sync handler.
-   * @type {DriveSyncHandler}
-   * @private
-   */
-  this.driveSyncHandler_ = new DriveSyncHandler(this.progressCenter);
-  this.driveSyncHandler_.addEventListener(
-      DriveSyncHandler.COMPLETED_EVENT,
-      function() { this.tryClose(); }.bind(this));
-
-  /**
-   * String assets.
-   * @type {Object.<string, string>}
-   */
-  this.stringData = null;
-
-  /**
-   * Callback list to be invoked after initialization.
-   * It turns to null after initialization.
-   *
-   * @type {Array.<function()>}
-   * @private
-   */
-  this.initializeCallbacks_ = [];
-
-  /**
-   * Last time when the background page can close.
-   *
-   * @type {number}
-   * @private
-   */
-  this.lastTimeCanClose_ = null;
-
-  // Seal self.
-  Object.seal(this);
-
-  // Initialize handlers.
-  chrome.fileBrowserHandler.onExecute.addListener(this.onExecute_.bind(this));
-  chrome.app.runtime.onLaunched.addListener(this.onLaunched_.bind(this));
-  chrome.app.runtime.onRestarted.addListener(this.onRestarted_.bind(this));
-  chrome.contextMenus.onClicked.addListener(
-      this.onContextMenuClicked_.bind(this));
-
-  // Fetch strings and initialize the context menu.
-  this.queue.run(function(callNextStep) {
-    chrome.fileBrowserPrivate.getStrings(function(strings) {
-      // Initialize string assets.
-      this.stringData = strings;
-      loadTimeData.data = strings;
-      this.initContextMenu_();
-
-      // Invoke initialize callbacks.
-      for (var i = 0; i < this.initializeCallbacks_.length; i++) {
-        this.initializeCallbacks_[i]();
-      }
-      this.initializeCallbacks_ = null;
-
-      callNextStep();
-    }.bind(this));
-  }.bind(this));
-}
-
-/**
- * A number of delay milliseconds from the first call of tryClose to the actual
- * close action.
- * @type {number}
- * @const
- * @private
- */
-Background.CLOSE_DELAY_MS_ = 5000;
-
-/**
- * Make a key of window geometry preferences for the given initial URL.
- * @param {string} url Initialize URL that the window has.
- * @return {string} Key of window geometry preferences.
- */
-Background.makeGeometryKey = function(url) {
-  return 'windowGeometry' + ':' + url;
-};
-
-/**
- * Key for getting and storing the last window state (maximized or not).
- * @const
- * @private
- */
-Background.MAXIMIZED_KEY_ = 'isMaximized';
-
-/**
- * Register callback to be invoked after initialization.
- * If the initialization is already done, the callback is invoked immediately.
- *
- * @param {function()} callback Initialize callback to be registered.
- */
-Background.prototype.ready = function(callback) {
-  if (this.initializeCallbacks_ !== null)
-    this.initializeCallbacks_.push(callback);
-  else
-    callback();
-};
-
-/**
- * Checks the current condition of background page and closes it if possible.
- */
-Background.prototype.tryClose = function() {
-  // If the file operation is going, the background page cannot close.
-  if (this.fileOperationManager.hasQueuedTasks() ||
-      this.driveSyncHandler_.syncing) {
-    this.lastTimeCanClose_ = null;
-    return;
-  }
-
-  var views = chrome.extension.getViews();
-  var closing = false;
-  for (var i = 0; i < views.length; i++) {
-    // If the window that is not the background page itself and it is not
-    // closing, the background page cannot close.
-    if (views[i] !== window && !views[i].closing) {
-      this.lastTimeCanClose_ = null;
-      return;
-    }
-    closing = closing || views[i].closing;
-  }
-
-  // If some windows are closing, or the background page can close but could not
-  // 5 seconds ago, We need more time for sure.
-  if (closing ||
-      this.lastTimeCanClose_ === null ||
-      Date.now() - this.lastTimeCanClose_ < Background.CLOSE_DELAY_MS_) {
-    if (this.lastTimeCanClose_ === null)
-      this.lastTimeCanClose_ = Date.now();
-    setTimeout(this.tryClose.bind(this), Background.CLOSE_DELAY_MS_);
-    return;
-  }
-
-  // Otherwise we can close the background page.
-  close();
-};
-
-/**
- * Gets similar windows, it means with the same initial url.
- * @param {string} url URL that the obtained windows have.
- * @return {Array.<AppWindow>} List of similar windows.
- */
-Background.prototype.getSimilarWindows = function(url) {
-  var result = [];
-  for (var appID in this.appWindows) {
-    if (this.appWindows[appID].contentWindow.appInitialURL === url)
-      result.push(this.appWindows[appID]);
-  }
-  return result;
-};
-
-/**
- * Wrapper for an app window.
- *
- * Expects the following from the app scripts:
- * 1. The page load handler should initialize the app using |window.appState|
- *    and call |util.platform.saveAppState|.
- * 2. Every time the app state changes the app should update |window.appState|
- *    and call |util.platform.saveAppState| .
- * 3. The app may have |unload| function to persist the app state that does not
- *    fit into |window.appState|.
- *
- * @param {string} url App window content url.
- * @param {string} id App window id.
- * @param {Object} options Options object to create it.
- * @constructor
- */
-function AppWindowWrapper(url, id, options) {
-  this.url_ = url;
-  this.id_ = id;
-  // Do deep copy for the template of options to assign customized params later.
-  this.options_ = JSON.parse(JSON.stringify(options));
-  this.window_ = null;
-  this.appState_ = null;
-  this.openingOrOpened_ = false;
-  this.queue = new AsyncUtil.Queue();
-  Object.seal(this);
-}
-
-AppWindowWrapper.prototype = {
-  /**
-   * @return {AppWindow} Wrapped application window.
-   */
-  get rawAppWindow() {
-    return this.window_;
-  }
-};
-
-/**
- * Focuses the window on the specified desktop.
- * @param {AppWindow} appWindow Application window.
- * @param {string=} opt_profileId The profiled ID of the target window. If it is
- *     dropped, the window is focused on the current window.
- */
-AppWindowWrapper.focusOnDesktop = function(appWindow, opt_profileId) {
-  new Promise(function(onFulfilled, onRejected) {
-    if (opt_profileId) {
-      onFulfilled(opt_profileId);
-    } else {
-      chrome.fileBrowserPrivate.getProfiles(function(profiles,
-                                                     currentId,
-                                                     displayedId) {
-        onFulfilled(currentId);
-      });
-    }
-  }).then(function(profileId) {
-    appWindow.contentWindow.chrome.fileBrowserPrivate.visitDesktop(
-        profileId, function() {
-      appWindow.focus();
-    });
-  });
-};
-
-/**
- * Shift distance to avoid overlapping windows.
- * @type {number}
- * @const
- */
-AppWindowWrapper.SHIFT_DISTANCE = 40;
-
-/**
- * Sets the icon of the window.
- * @param {string} iconPath Path of the icon.
- */
-AppWindowWrapper.prototype.setIcon = function(iconPath) {
-  this.window_.setIcon(iconPath);
-};
-
-/**
- * Opens the window.
- *
- * @param {Object} appState App state.
- * @param {boolean} reopen True if the launching is triggered automatically.
- *     False otherwise.
- * @param {function()=} opt_callback Completion callback.
- */
-AppWindowWrapper.prototype.launch = function(appState, reopen, opt_callback) {
-  // Check if the window is opened or not.
-  if (this.openingOrOpened_) {
-    console.error('The window is already opened.');
-    if (opt_callback)
-      opt_callback();
-    return;
-  }
-  this.openingOrOpened_ = true;
-
-  // Save application state.
-  this.appState_ = appState;
-
-  // Get similar windows, it means with the same initial url, eg. different
-  // main windows of Files.app.
-  var similarWindows = background.getSimilarWindows(this.url_);
-
-  // Restore maximized windows, to avoid hiding them to tray, which can be
-  // confusing for users.
-  this.queue.run(function(callback) {
-    for (var index = 0; index < similarWindows.length; index++) {
-      if (similarWindows[index].isMaximized()) {
-        var createWindowAndRemoveListener = function() {
-          similarWindows[index].onRestored.removeListener(
-              createWindowAndRemoveListener);
-          callback();
-        };
-        similarWindows[index].onRestored.addListener(
-            createWindowAndRemoveListener);
-        similarWindows[index].restore();
-        return;
-      }
-    }
-    // If no maximized windows, then create the window immediately.
-    callback();
-  });
-
-  // Obtains the last geometry and window state (maximized or not).
-  var lastBounds;
-  var isMaximized = false;
-  this.queue.run(function(callback) {
-    var boundsKey = Background.makeGeometryKey(this.url_);
-    var maximizedKey = Background.MAXIMIZED_KEY_;
-    chrome.storage.local.get([boundsKey, maximizedKey], function(preferences) {
-      if (!chrome.runtime.lastError) {
-        lastBounds = preferences[boundsKey];
-        isMaximized = preferences[maximizedKey];
-      }
-      callback();
-    });
-  }.bind(this));
-
-  // Closure creating the window, once all preprocessing tasks are finished.
-  this.queue.run(function(callback) {
-    // Apply the last bounds.
-    if (lastBounds)
-      this.options_.bounds = lastBounds;
-    if (isMaximized)
-      this.options_.state = 'maximized';
-
-    // Create a window.
-    chrome.app.window.create(this.url_, this.options_, function(appWindow) {
-      this.window_ = appWindow;
-      callback();
-    }.bind(this));
-  }.bind(this));
-
-  // After creating.
-  this.queue.run(function(callback) {
-    // If there is another window in the same position, shift the window.
-    var makeBoundsKey = function(bounds) {
-      return bounds.left + '/' + bounds.top;
-    };
-    var notAvailablePositions = {};
-    for (var i = 0; i < similarWindows.length; i++) {
-      var key = makeBoundsKey(similarWindows[i].getBounds());
-      notAvailablePositions[key] = true;
-    }
-    var candidateBounds = this.window_.getBounds();
-    while (true) {
-      var key = makeBoundsKey(candidateBounds);
-      if (!notAvailablePositions[key])
-        break;
-      // Make the position available to avoid an infinite loop.
-      notAvailablePositions[key] = false;
-      var nextLeft = candidateBounds.left + AppWindowWrapper.SHIFT_DISTANCE;
-      var nextRight = nextLeft + candidateBounds.width;
-      candidateBounds.left = nextRight >= screen.availWidth ?
-          nextRight % screen.availWidth : nextLeft;
-      var nextTop = candidateBounds.top + AppWindowWrapper.SHIFT_DISTANCE;
-      var nextBottom = nextTop + candidateBounds.height;
-      candidateBounds.top = nextBottom >= screen.availHeight ?
-          nextBottom % screen.availHeight : nextTop;
-    }
-    this.window_.moveTo(candidateBounds.left, candidateBounds.top);
-
-    // Save the properties.
-    var appWindow = this.window_;
-    background.appWindows[this.id_] = appWindow;
-    var contentWindow = appWindow.contentWindow;
-    contentWindow.appID = this.id_;
-    contentWindow.appState = this.appState_;
-    contentWindow.appReopen = reopen;
-    contentWindow.appInitialURL = this.url_;
-    if (window.IN_TEST)
-      contentWindow.IN_TEST = true;
-
-    // Register event listeners.
-    appWindow.onBoundsChanged.addListener(this.onBoundsChanged_.bind(this));
-    appWindow.onClosed.addListener(this.onClosed_.bind(this));
-
-    // Callback.
-    if (opt_callback)
-      opt_callback();
-    callback();
-  }.bind(this));
-};
-
-/**
- * Handles the onClosed extension API event.
- * @private
- */
-AppWindowWrapper.prototype.onClosed_ = function() {
-  // Remember the last window state (maximized or normal).
-  var preferences = {};
-  preferences[Background.MAXIMIZED_KEY_] = this.window_.isMaximized();
-  chrome.storage.local.set(preferences);
-
-  // Unload the window.
-  var appWindow = this.window_;
-  var contentWindow = this.window_.contentWindow;
-  if (contentWindow.unload)
-    contentWindow.unload();
-  this.window_ = null;
-  this.openingOrOpened_ = false;
-
-  // Updates preferences.
-  if (contentWindow.saveOnExit) {
-    contentWindow.saveOnExit.forEach(function(entry) {
-      util.AppCache.update(entry.key, entry.value);
-    });
-  }
-  chrome.storage.local.remove(this.id_);  // Forget the persisted state.
-
-  // Remove the window from the set.
-  delete background.appWindows[this.id_];
-
-  // If there is no application window, reset window ID.
-  if (!Object.keys(background.appWindows).length)
-    nextFileManagerWindowID = 0;
-  background.tryClose();
-};
-
-/**
- * Handles onBoundsChanged extension API event.
- * @private
- */
-AppWindowWrapper.prototype.onBoundsChanged_ = function() {
-  if (!this.window_.isMaximized()) {
-    var preferences = {};
-    preferences[Background.makeGeometryKey(this.url_)] =
-        this.window_.getBounds();
-    chrome.storage.local.set(preferences);
-  }
-};
-
-/**
- * Wrapper for a singleton app window.
- *
- * In addition to the AppWindowWrapper requirements the app scripts should
- * have |reload| method that re-initializes the app based on a changed
- * |window.appState|.
- *
- * @param {string} url App window content url.
- * @param {Object|function()} options Options object or a function to return it.
- * @constructor
- */
-function SingletonAppWindowWrapper(url, options) {
-  AppWindowWrapper.call(this, url, url, options);
-}
-
-/**
- * Inherits from AppWindowWrapper.
- */
-SingletonAppWindowWrapper.prototype = {__proto__: AppWindowWrapper.prototype};
-
-/**
- * Open the window.
- *
- * Activates an existing window or creates a new one.
- *
- * @param {Object} appState App state.
- * @param {boolean} reopen True if the launching is triggered automatically.
- *     False otherwise.
- * @param {function()=} opt_callback Completion callback.
- */
-SingletonAppWindowWrapper.prototype.launch =
-    function(appState, reopen, opt_callback) {
-  // If the window is not opened yet, just call the parent method.
-  if (!this.openingOrOpened_) {
-    AppWindowWrapper.prototype.launch.call(
-        this, appState, reopen, opt_callback);
-    return;
-  }
-
-  // If the window is already opened, reload the window.
-  // The queue is used to wait until the window is opened.
-  this.queue.run(function(nextStep) {
-    this.window_.contentWindow.appState = appState;
-    this.window_.contentWindow.appReopen = reopen;
-    this.window_.contentWindow.reload();
-    if (opt_callback)
-      opt_callback();
-    nextStep();
-  }.bind(this));
-};
-
-/**
- * Reopen a window if its state is saved in the local storage.
- * @param {function()=} opt_callback Completion callback.
- */
-SingletonAppWindowWrapper.prototype.reopen = function(opt_callback) {
-  chrome.storage.local.get(this.id_, function(items) {
-    var value = items[this.id_];
-    if (!value) {
-      opt_callback && opt_callback();
-      return;  // No app state persisted.
-    }
-
-    try {
-      var appState = JSON.parse(value);
-    } catch (e) {
-      console.error('Corrupt launch data for ' + this.id_, value);
-      opt_callback && opt_callback();
-      return;
-    }
-    this.launch(appState, true, opt_callback);
-  }.bind(this));
-};
-
-/**
- * Prefix for the file manager window ID.
- */
-var FILES_ID_PREFIX = 'files#';
-
-/**
- * Regexp matching a file manager window ID.
- */
-var FILES_ID_PATTERN = new RegExp('^' + FILES_ID_PREFIX + '(\\d*)$');
-
-/**
- * Value of the next file manager window ID.
- */
-var nextFileManagerWindowID = 0;
-
-/**
- * File manager window create options.
- * @type {Object}
- * @const
- */
-var FILE_MANAGER_WINDOW_CREATE_OPTIONS = Object.freeze({
-  bounds: Object.freeze({
-    left: Math.round(window.screen.availWidth * 0.1),
-    top: Math.round(window.screen.availHeight * 0.1),
-    width: Math.round(window.screen.availWidth * 0.8),
-    height: Math.round(window.screen.availHeight * 0.8)
-  }),
-  minWidth: 480,
-  minHeight: 240,
-  frame: 'none',
-  hidden: true,
-  transparentBackground: true
-});
-
-/**
- * @param {Object=} opt_appState App state.
- * @param {number=} opt_id Window id.
- * @param {LaunchType=} opt_type Launch type. Default: ALWAYS_CREATE.
- * @param {function(string)=} opt_callback Completion callback with the App ID.
- */
-function launchFileManager(opt_appState, opt_id, opt_type, opt_callback) {
-  var type = opt_type || LaunchType.ALWAYS_CREATE;
-
-  // Wait until all windows are created.
-  background.queue.run(function(onTaskCompleted) {
-    // Check if there is already a window with the same URL. If so, then
-    // reuse it instead of opening a new one.
-    if (type == LaunchType.FOCUS_SAME_OR_CREATE ||
-        type == LaunchType.FOCUS_ANY_OR_CREATE) {
-      if (opt_appState) {
-        for (var key in background.appWindows) {
-          if (!key.match(FILES_ID_PATTERN))
-            continue;
-
-          var contentWindow = background.appWindows[key].contentWindow;
-          if (!contentWindow.appState)
-            continue;
-
-          // Different current directories.
-          if (opt_appState.currentDirectoryURL !==
-                  contentWindow.appState.currentDirectoryURL) {
-            continue;
-          }
-
-          // Selection URL specified, and it is different.
-          if (opt_appState.selectionURL &&
-                  opt_appState.selectionURL !==
-                  contentWindow.appState.selectionURL) {
-            continue;
-          }
-
-          AppWindowWrapper.focusOnDesktop(
-              background.appWindows[key], opt_appState.displayedId);
-          if (opt_callback)
-            opt_callback(key);
-          onTaskCompleted();
-          return;
-        }
-      }
-    }
-
-    // Focus any window if none is focused. Try restored first.
-    if (type == LaunchType.FOCUS_ANY_OR_CREATE) {
-      // If there is already a focused window, then finish.
-      for (var key in background.appWindows) {
-        if (!key.match(FILES_ID_PATTERN))
-          continue;
-
-        // The isFocused() method should always be available, but in case
-        // Files.app's failed on some error, wrap it with try catch.
-        try {
-          if (background.appWindows[key].contentWindow.isFocused()) {
-            if (opt_callback)
-              opt_callback(key);
-            onTaskCompleted();
-            return;
-          }
-        } catch (e) {
-          console.error(e.message);
-        }
-      }
-      // Try to focus the first non-minimized window.
-      for (var key in background.appWindows) {
-        if (!key.match(FILES_ID_PATTERN))
-          continue;
-
-        if (!background.appWindows[key].isMinimized()) {
-          AppWindowWrapper.focusOnDesktop(
-              background.appWindows[key], (opt_appState || {}).displayedId);
-          if (opt_callback)
-            opt_callback(key);
-          onTaskCompleted();
-          return;
-        }
-      }
-      // Restore and focus any window.
-      for (var key in background.appWindows) {
-        if (!key.match(FILES_ID_PATTERN))
-          continue;
-
-        AppWindowWrapper.focusOnDesktop(
-            background.appWindows[key], (opt_appState || {}).displayedId);
-        if (opt_callback)
-          opt_callback(key);
-        onTaskCompleted();
-        return;
-      }
-    }
-
-    // Create a new instance in case of ALWAYS_CREATE type, or as a fallback
-    // for other types.
-
-    var id = opt_id || nextFileManagerWindowID;
-    nextFileManagerWindowID = Math.max(nextFileManagerWindowID, id + 1);
-    var appId = FILES_ID_PREFIX + id;
-
-    var appWindow = new AppWindowWrapper(
-        'main.html',
-        appId,
-        FILE_MANAGER_WINDOW_CREATE_OPTIONS);
-    appWindow.launch(opt_appState || {}, false, function() {
-      AppWindowWrapper.focusOnDesktop(
-          appWindow.window_, (opt_appState || {}).displayedId);
-      if (opt_callback)
-        opt_callback(appId);
-      onTaskCompleted();
-    });
-  });
-}
-
-/**
- * Executes a file browser task.
- *
- * @param {string} action Task id.
- * @param {Object} details Details object.
- * @private
- */
-Background.prototype.onExecute_ = function(action, details) {
-  var urls = details.entries.map(function(e) { return e.toURL(); });
-
-  switch (action) {
-    case 'play':
-      launchAudioPlayer({items: urls, position: 0});
-      break;
-
-    default:
-      var launchEnable = null;
-      var queue = new AsyncUtil.Queue();
-      queue.run(function(nextStep) {
-        // If it is not auto-open (triggered by mounting external devices), we
-        // always launch Files.app.
-        if (action != 'auto-open') {
-          launchEnable = true;
-          nextStep();
-          return;
-        }
-        // If the disable-default-apps flag is on, Files.app is not opened
-        // automatically on device mount not to obstruct the manual test.
-        chrome.commandLinePrivate.hasSwitch('disable-default-apps',
-                                            function(flag) {
-          launchEnable = !flag;
-          nextStep();
-        });
-      });
-      queue.run(function(nextStep) {
-        if (!launchEnable) {
-          nextStep();
-          return;
-        }
-
-        // Every other action opens a Files app window.
-        var appState = {
-          params: {
-            action: action
-          },
-          // It is not allowed to call getParent() here, since there may be
-          // no permissions to access it at this stage. Therefore we are passing
-          // the selectionURL only, and the currentDirectory will be resolved
-          // later.
-          selectionURL: details.entries[0].toURL()
-        };
-        // For mounted devices just focus any Files.app window. The mounted
-        // volume will appear on the navigation list.
-        var type = action == 'auto-open' ? LaunchType.FOCUS_ANY_OR_CREATE :
-            LaunchType.FOCUS_SAME_OR_CREATE;
-        launchFileManager(appState, /* App ID */ undefined, type, nextStep);
-      });
-      break;
-  }
-};
-
-/**
- * Icon of the audio player.
- * TODO(yoshiki): Consider providing an exact size icon, instead of relying
- * on downsampling by ash.
- *
- * @type {string}
- * @const
- */
-var AUDIO_PLAYER_ICON = 'audio_player/icons/audio-player-64.png';
-
-// The instance of audio player. Until it's ready, this is null.
-var audioPlayer = null;
-
-// Queue to serializes the initialization, launching and reloading of the audio
-// player, so races won't happen.
-var audioPlayerInitializationQueue = new AsyncUtil.Queue();
-
-audioPlayerInitializationQueue.run(function(callback) {
-  // TODO(yoshiki): Remove '--file-manager-enable-new-audio-player' flag after
-  // the feature is launched.
-  var newAudioPlayerEnabled = true;
-
-  var audioPlayerHTML =
-      newAudioPlayerEnabled ? 'audio_player.html' : 'mediaplayer.html';
-
-  /**
-   * Audio player window create options.
-   * @type {Object}
-   */
-  var audioPlayerCreateOptions = Object.freeze({
-      type: 'panel',
-      hidden: true,
-      minHeight:
-          newAudioPlayerEnabled ?
-              (44 + 73) :  // 44px: track, 73px: controller
-              (35 + 58),  // 35px: track, 58px: controller
-      minWidth: newAudioPlayerEnabled ? 292 : 280,
-      height: newAudioPlayerEnabled ? (44 + 73) : (35 + 58),  // collapsed
-      width: newAudioPlayerEnabled ? 292 : 280,
-  });
-
-  audioPlayer = new SingletonAppWindowWrapper(audioPlayerHTML,
-                                              audioPlayerCreateOptions);
-  callback();
-});
-
-/**
- * Launches the audio player.
- * @param {Object} playlist Playlist.
- * @param {string=} opt_displayedId ProfileID of the desktop where the audio
- *     player should show.
- */
-function launchAudioPlayer(playlist, opt_displayedId) {
-  audioPlayerInitializationQueue.run(function(callback) {
-    audioPlayer.launch(playlist, false, function(appWindow) {
-      audioPlayer.setIcon(AUDIO_PLAYER_ICON);
-      AppWindowWrapper.focusOnDesktop(audioPlayer.rawAppWindow,
-                                      opt_displayedId);
-    });
-    callback();
-  });
-}
-
-/**
- * Launches the app.
- * @private
- */
-Background.prototype.onLaunched_ = function() {
-  if (nextFileManagerWindowID == 0) {
-    // The app just launched. Remove window state records that are not needed
-    // any more.
-    chrome.storage.local.get(function(items) {
-      for (var key in items) {
-        if (items.hasOwnProperty(key)) {
-          if (key.match(FILES_ID_PATTERN))
-            chrome.storage.local.remove(key);
-        }
-      }
-    });
-  }
-  launchFileManager(null, null, LaunchType.FOCUS_ANY_OR_CREATE);
-};
-
-/**
- * Restarted the app, restore windows.
- * @private
- */
-Background.prototype.onRestarted_ = function() {
-  // Reopen file manager windows.
-  chrome.storage.local.get(function(items) {
-    for (var key in items) {
-      if (items.hasOwnProperty(key)) {
-        var match = key.match(FILES_ID_PATTERN);
-        if (match) {
-          var id = Number(match[1]);
-          try {
-            var appState = JSON.parse(items[key]);
-            launchFileManager(appState, id);
-          } catch (e) {
-            console.error('Corrupt launch data for ' + id);
-          }
-        }
-      }
-    }
-  });
-
-  // Reopen audio player.
-  audioPlayerInitializationQueue.run(function(callback) {
-    audioPlayer.reopen(function() {
-      // If the audioPlayer is reopened, change its window's icon. Otherwise
-      // there is no reopened window so just skip the call of setIcon.
-      if (audioPlayer.rawAppWindow)
-        audioPlayer.setIcon(AUDIO_PLAYER_ICON);
-    });
-    callback();
-  });
-};
-
-/**
- * Handles clicks on a custom item on the launcher context menu.
- * @param {OnClickData} info Event details.
- * @private
- */
-Background.prototype.onContextMenuClicked_ = function(info) {
-  if (info.menuItemId == 'new-window') {
-    // Find the focused window (if any) and use it's current url for the
-    // new window. If not found, then launch with the default url.
-    for (var key in background.appWindows) {
-      try {
-        if (background.appWindows[key].contentWindow.isFocused()) {
-          var appState = {
-            // Do not clone the selection url, only the current directory.
-            currentDirectoryURL: background.appWindows[key].contentWindow.
-                appState.currentDirectoryURL
-          };
-          launchFileManager(appState);
-          return;
-        }
-      } catch (ignore) {
-        // The isFocused method may not be defined during initialization.
-        // Therefore, wrapped with a try-catch block.
-      }
-    }
-
-    // Launch with the default URL.
-    launchFileManager();
-  }
-};
-
-/**
- * Initializes the context menu. Recreates if already exists.
- * @private
- */
-Background.prototype.initContextMenu_ = function() {
-  try {
-    // According to the spec [1], the callback is optional. But no callback
-    // causes an error for some reason, so we call it with null-callback to
-    // prevent the error. http://crbug.com/353877
-    // - [1] https://developer.chrome.com/extensions/contextMenus#method-remove
-    chrome.contextMenus.remove('new-window', function() {});
-  } catch (ignore) {
-    // There is no way to detect if the context menu is already added, therefore
-    // try to recreate it every time.
-  }
-  chrome.contextMenus.create({
-    id: 'new-window',
-    contexts: ['launcher'],
-    title: str('NEW_WINDOW_BUTTON_LABEL')
-  });
-};
-
-/**
- * Singleton instance of Background.
- * @type {Background}
- */
-window.background = new Background();