Add chrome.fileSystem.GetVolumeList().

chrome/test/data/chromeos/app_mode/get_volume_list/src/background.js

Index: chrome/test/data/chromeos/app_mode/get_volume_list/src/background.js
diff --git a/chrome/test/data/chromeos/app_mode/get_volume_list/src/background.js b/chrome/test/data/chromeos/app_mode/get_volume_list/src/background.js
new file mode 100644
index 0000000000000000000000000000000000000000..c9447e8c1de52d13c9198ab05e501190562b62fa
--- /dev/null
+++ b/chrome/test/data/chromeos/app_mode/get_volume_list/src/background.js
@@ -0,0 +1,15 @@
+// Copyright 2015 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.
+
+chrome.test.runTests([
+  function getVolumeList() {
+    chrome.fileSystem.getVolumeList(
+        chrome.test.callbackPass(function(volumeList) {
+          // Drive is not exposed in kiosk session.
+          chrome.test.assertEq(1, volumeList.length);
+          chrome.test.assertEq('downloads:Downloads', volumeList[0].volumeId);
+          chrome.test.assertTrue(volumeList[0].writable);
+        }));
+  }
+]);