Revert of Add a media scanner convenience class.

ui/file_manager/file_manager/background/js/media_scanner.js

Index: ui/file_manager/file_manager/background/js/media_scanner.js
diff --git a/ui/file_manager/file_manager/background/js/media_scanner.js b/ui/file_manager/file_manager/background/js/media_scanner.js
deleted file mode 100644
index 7c744b2e214768e5bcc90d94c3b31f1c1f8f2c6b..0000000000000000000000000000000000000000
--- a/ui/file_manager/file_manager/background/js/media_scanner.js
+++ /dev/null
@@ -1,65 +0,0 @@
-// 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.
-
-/**
- * Recursively scans through a list of given files and directories, and creates
- * a list of media files.
- *
- * @param {!Array.<!Entry>} entries A list of file and directory entries.  File
- *     entries are added directly to the media list; directory entries are
- *     recursively traversed to find files, which are added to the media list.
- * @constructor
- */
-function MediaScanner(entries) {
-  /** @private {!Promise<!Array<!FileEntry>>} */
-  this.filesPromise_ = this.scan_(entries);
-}
-
-/**
- * Scans a list of directory and file entries, returning image and video files.
- * @param {!Array<!Entry>} entries
- */
-MediaScanner.prototype.scan_ = function(entries) {
-  /**
-   * Returns files and directories found under the given Entry.
-   * @param {!Entry} entry
-   * @return {!Promise<!Array<!Entry>>}
-   */
-  var scanRecurse = function(entry) {
-    return new Promise(function(resolve, reject) {
-      fileOperationUtil.resolveRecursively(entry, resolve, reject);
-    });
-  };
-
-  /**
-   * Flattens a nested list of Entries.
-   * @param {!Array<!Array<!Entry>>} array
-   * @return {!Array<!Entry>}
-   */
-  var flatten = function(array) {
-    return array.reduce(function(prev, curr) {
-      return prev.concat(curr);
-    }, []);
-  };
-
-  /**
-   * Filters non-image and non-video files out of the given list.
-   * @param {!Array<!Entry>} array
-   * @return {!Array<!Entry>}
-   */
-  var filter = function(array) {
-    return array.filter(FileType.isImageOrVideo);
-  };
-
-  return Promise.all(entries.map(scanRecurse))
-      .then(flatten)
-      .then(filter);
-};
-
-/**
- * @return {!Promise<!Array<!FileEntry>>}
- */
-MediaScanner.prototype.getFiles = function() {
-  return this.filesPromise_;
-};