file_manager: Move mount test stuff to c/t/d/extensions/api_test/file_browser

chrome/test/data/extensions/api_test/file_browser/mount_test/test.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.
 
 // These have to be sync'd with file_browser_private_apitest.cc
 var expectedVolume1 = {
   devicePath: 'device_path1',
   mountPath: 'removable/mount_path1',
   systemPath: 'system_path1',
   filePath: 'file_path1',
@@ skipping 179 matching lines @@
           chrome.test.assertEq(result.length, expectedMountPoints.length,
               'getMountPoints returned wrong number of mount points.');
           for (var i = 0; i < expectedMountPoints.length; i++) {
             chrome.test.assertTrue(
                 validateObject(result[i], expectedMountPoints[i], 'mountPoint'),
                 'getMountPoints result[' + i + '] not as expected');
           }
     }));
   }
 ]);