Return null in getLocationInfo for Drive files outside of virtual mount points.

chrome/browser/resources/file_manager/background/js/volume_manager.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';
 
 /**
  * Represents each volume, such as "drive", "download directory", each "USB
  * flush storage", or "mounted zip archive" etc.
  *
@@ skipping 677 matching lines @@
     if ((entry.fullPath + '/').indexOf(volumeInfo.mountPath + '/root/') === 0) {
       rootPath = volumeInfo.mountPath + '/root';
       rootType = RootType.DRIVE;
       isReadOnly = volumeInfo.isReadOnly;
     } else if ((entry.fullPath + '/').indexOf(
                    volumeInfo.mountPath + '/other/') === 0) {
       rootPath = volumeInfo.mountPath + '/other';
       rootType = RootType.DRIVE_OTHER;
       isReadOnly = true;
     } else {
-      throw new Error(entry.fullPath + ' is an invalid drive path.');
+      // Accessing Drive files outside of /drive/root and /drive/other is not
+      // allowed, but can happen. Therefore returning null.
+      return null;
     }
   } else {
     // Otherwise, root path is same with a mount path of the volume.
     rootPath = volumeInfo.mountPath;
     switch (volumeInfo.volumeType) {
       case util.VolumeType.DOWNLOADS:
         rootType = RootType.DOWNLOADS;
         break;
       case util.VolumeType.REMOVABLE:
         rootType = RootType.REMOVABLE;
         break;
       case util.VolumeType.ARCHIVE:
         rootType = RootType.ARCHIVE;
         break;
       case util.VolumeType.CLOUD_DEVICE:
         rootType = RootType.CLOUD_DEVICE;
         break;
       default:
+        // Programming error, throw an exception.
         throw new Error('Invalid volume type: ' + volumeInfo.volumeType);
     }
     isReadOnly = volumeInfo.isReadOnly;
   }
   var isRootEntry = (entry.fullPath.substr(0, rootPath.length) || '/') ===
       entry.fullPath;
 
   return new EntryLocation(volumeInfo, rootType, isRootEntry, isReadOnly);
 };
 
@@ skipping 132 matching lines @@
       this.isDriveBased;
 
   /**
    * Whether the entry is read only or not.
    * @type {boolean}
    */
   this.isReadOnly = isReadOnly;
 
   Object.freeze(this);
 }