Removed most of path utility functions in Files app.

chrome/browser/resources/file_manager/foreground/js/directory_model.js

 // 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';
 
 // If directory files changes too often, don't rescan directory more than once
 // per specified interval
 var SIMULTANEOUS_RESCAN_INTERVAL = 1000;
 // Used for operations that require almost instant rescan.
@@ skipping 762 matching lines @@
   // since the current directory is initializing now.
   if (this.getCurrentDirEntry() &&
       !this.volumeManager_.getVolumeInfo(this.getCurrentDirEntry())) {
     this.volumeManager_.getDefaultDisplayRoot(function(displayRoot) {
       this.changeDirectoryEntry(displayRoot);
     }.bind(this));
   }
 };
 
 /**
- * Check if the root of the given path is mountable or not.
- *
- * @param {string} path Path.
- * @return {boolean} Return true, if the given path is under mountable root.
- *     Otherwise, return false.
- */
-DirectoryModel.isMountableRoot = function(path) {
-  var rootType = PathUtil.getRootType(path);
-  switch (rootType) {
-    case RootType.DOWNLOADS:
-      return false;
-    case RootType.ARCHIVE:
-    case RootType.REMOVABLE:
-    case RootType.DRIVE:
-      return true;
-    default:
-      throw new Error('Unknown root type!');
-  }
-};
-
-/**
  * Performs search and displays results. The search type is dependent on the
  * current directory. If we are currently on drive, server side content search
  * over drive mount point. If the current directory is not on the drive, file
  * name search over current directory will be performed.
  *
  * @param {string} query Query that will be searched for.
  * @param {function(Event)} onSearchRescan Function that will be called when the
  *     search directory is rescanned (i.e. search results are displayed).
  * @param {function()} onClearSearch Function to be called when search state
  *     gets cleared.
@@ skipping 129 matching lines @@
   if (this.onSearchCompleted_) {
     this.removeEventListener('scan-completed', this.onSearchCompleted_);
     this.onSearchCompleted_ = null;
   }
 
   if (this.onClearSearch_) {
     this.onClearSearch_();
     this.onClearSearch_ = null;
   }
 };