Add the chrome.fileSystem.onVolumeListChanged event.

chrome/test/data/extensions/api_test/file_system/on_volume_list_changed/manifest.json

Index: chrome/test/data/extensions/api_test/file_system/on_volume_list_changed/manifest.json
diff --git a/chrome/test/data/extensions/api_test/file_system/request_file_system_whitelisted_component/manifest.json b/chrome/test/data/extensions/api_test/file_system/on_volume_list_changed/manifest.json
similarity index 76%
copy from chrome/test/data/extensions/api_test/file_system/request_file_system_whitelisted_component/manifest.json
copy to chrome/test/data/extensions/api_test/file_system/on_volume_list_changed/manifest.json
index 908c73ce31306b689c7079a4dcb4e10005ac9888..63c7f80650c1ee1f26e11e2d9426273b7f286f04 100644
--- a/chrome/test/data/extensions/api_test/file_system/request_file_system_whitelisted_component/manifest.json
+++ b/chrome/test/data/extensions/api_test/file_system/on_volume_list_changed/manifest.json
@@ -1,14 +1,16 @@
 {
   // chrome-extension://pkplfbidichfdicaijlchgnapepdginl
   "key": "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAtDfX9dHNh948bt00YhZBm3P6E5QLaOt+v8kXVtibQfiPtOD2FTScB/f0wX/EQWVO7BkaSOsRkTPcPIgocyMPYr2FLgqGLFlYT9nQpKJZUFNF5oJ5rG6Nv7ppf4zEB3j6da1IBRTz2yOZ+6O1TMZxol/V62/QcqrJeggsHTEPGLdr9Ua4b1Ka0xKJnJngZljsbw93FI1o+P9dAh5BS6wTPiZI/vmJVjvMTkSTnaZ3n9Go2t7A0XLcSxLcVyuLAd2mAvSN0mIviOukdM66wr7llif71nKuUt+4qvlr/r9HfwzN6pA4jkwhtS1UD+3CmB+wsHwsnohNcuu4FIQ6rgq/7QIDAQAB",
-  "name": "chrome.fileSystem.requestFileSystem test for whitelisted components",
+  "name": "chrome.fileSystem.onVolumeListChanged test",
   "version": "0.1",
-  "description": "Test for requesting file systems via chrome.fileSystem.requestFileSystem by whitelisted components.",
+  "description": "Test for notifying about volume list changes.",
   "app": {
     "background": {
       "scripts": ["background.js"]
     }
   },
+  "kiosk_only": true,
+  "kiosk_enabled": true,
   "permissions": [
     {
       "fileSystem": ["requestFileSystem"]