Add support for directory access to the file system API.

chrome/test/data/extensions/api_test/file_system/open_directory_with_write/test_util.js

Index: chrome/test/data/extensions/api_test/file_system/open_directory_with_write/test_util.js
diff --git a/chrome/test/data/extensions/api_test/file_system/test_util.js b/chrome/test/data/extensions/api_test/file_system/open_directory_with_write/test_util.js
similarity index 65%
copy from chrome/test/data/extensions/api_test/file_system/test_util.js
copy to chrome/test/data/extensions/api_test/file_system/open_directory_with_write/test_util.js
index a768b029fbdfbdd14813c457d1bb741f3f5993ca..f0b37f739b8e8986fe3047d2e8669299befa7316 100644
--- a/chrome/test/data/extensions/api_test/file_system/test_util.js
+++ b/chrome/test/data/extensions/api_test/file_system/open_directory_with_write/test_util.js
@@ -2,9 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// This is a duplicate of the file test_util in
+// This is a modified duplicate of the file test_util in
 // chrome/test/data/extensions/api_test/file_system
 
+// TODO(sammc): Merge the changes back to the original test_util.js. See
+// http://crbug.com/280942.
 function checkEntry(entry, expectedName, isNew, shouldBeWritable) {
   chrome.test.assertEq(expectedName, entry.name);
 
@@ -36,19 +38,23 @@ function checkEntry(entry, expectedName, isNew, shouldBeWritable) {
           } else {
             if (shouldBeWritable) {
               // Get a new entry and check the data got to disk.
-              chrome.fileSystem.chooseEntry(chrome.test.callbackPass(
-                  function(readEntry) {
-                readEntry.file(chrome.test.callback(function(readFile) {
-                  var readReader = new FileReader();
-                  readReader.onloadend = function(e) {
-                    chrome.test.assertEq(readReader.result.indexOf("HoHoHo!"),
-                                         0);
-                    chrome.test.succeed();
-                  };
-                  readReader.onerror = function(e) {
-                    chrome.test.fail("Failed to read file after write.");
-                  };
-                  readReader.readAsText(readFile);
+              chrome.fileSystem.chooseEntry(
+                  {type: 'openDirectory'}, chrome.test.callbackPass(
+                      function(directoryEntry) {
+                directoryEntry.getFile(
+                    entry.name, {}, chrome.test.callback(function(readEntry) {
+                  readEntry.file(chrome.test.callback(function(readFile) {
+                    var readReader = new FileReader();
+                    readReader.onloadend = function(e) {
+                      chrome.test.assertEq(readReader.result.indexOf("HoHoHo!"),
+                                           0);
+                      chrome.test.succeed();
+                    };
+                    readReader.onerror = function(e) {
+                      chrome.test.fail("Failed to read file after write.");
+                    };
+                    readReader.readAsText(readFile);
+                  }));
                 }));
               }));
             } else {