Add support to mime types in Files app UI.

ui/file_manager/integration_tests/gallery/open_image_files.js

 // 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.
 
 'use strict';
 
 /**
  * Runs a test to open a single image.
  *
  * @param {string} testVolumeName Test volume name passed to the addEntries
@@ skipping 49 matching lines @@
 
 /**
  * Runs a test to open multiple images.
  *
  * @param {string} testVolumeName Test volume name passed to the addEntries
  *     function. Either 'drive' or 'local'.
  * @param {VolumeManagerCommon.VolumeType} volumeType Volume type.
  * @return {Promise} Promise to be fulfilled with on success.
  */
 function openMultipleImages(testVolumeName, volumeType) {
-  var testEntries = [ENTRIES.desktop, ENTRIES.image2, ENTRIES.image3];
+  var testEntries = [ENTRIES.desktop, ENTRIES.image3];
   var launchedPromise = launch(testVolumeName, volumeType, testEntries);
   return launchedPromise.then(function(args) {
     var appId = args.appId;
     var rootElementPromise =
         gallery.waitForElement(appId, '.gallery[mode="mosaic"]');
     var tilesPromise = repeatUntil(function() {
       return gallery.callRemoteTestUtil(
           'queryAllElements',
           appId,
           ['.mosaic-tile']
       ).then(function(tiles) {
-        if (tiles.length !== 3)
-          return pending('The number of tiles is expected 3, but is %d',
+        if (tiles.length !== 2)
+          return pending('The number of tiles is expected 2, but is %d',
                          tiles.length);
         return tiles;
       });
     });
     return Promise.all([rootElementPromise, tilesPromise]);
   });
 }
 
 /**
  * The openSingleImage test for Downloads.
@@ skipping 19 matching lines @@
   return openMultipleImages('local', 'downloads');
 };
 
 /**
  * The openMultiImages test for Google Drive.
  * @return {Promise} Promise to be fulfilled with on success.
  */
 testcase.openMultipleImagesOnDrive = function() {
   return openMultipleImages('drive', 'drive');
 };