Files.app: Add a test to open a file dialog box.

ui/file_manager/file_manager/manifest.json

Index: ui/file_manager/file_manager/manifest.json
diff --git a/ui/file_manager/file_manager/manifest.json b/ui/file_manager/file_manager/manifest.json
index edba2c522b71d817923999022eb07c53d1c24770..024e31121e8336223f836049a6d0a1ea0de00488 100644
--- a/ui/file_manager/file_manager/manifest.json
+++ b/ui/file_manager/file_manager/manifest.json
@@ -16,30 +16,30 @@
     "256": "common/images/icon256.png"
   },
   "permissions": [
+    // Comment out chrome:// permissions to debug on a desktop browser.
+    "chrome://extension-icon/",
+    "chrome://resources/",
+    "chrome://theme/",
+    "clipboardRead",
+    "clipboardWrite",
+    "commandLinePrivate",
     "contextMenus",
-    "experimental",
     "echoPrivate",
-    "storage",
+    "experimental",
     "fileBrowserHandler",
     "fileBrowserPrivate",
     "fullscreen",
-    "mediaPlayerPrivate",
+    "https://*.googleusercontent.com/",
+    "https://docs.google.com/",
+    "https://drive.google.com/",
     "mediaGalleriesPrivate",
+    "mediaPlayerPrivate",
     "metricsPrivate",
     "notifications",
-    "commandLinePrivate",
-    "unlimitedStorage",
-    "webview",
-    // Comment out chrome:// permissions to debug on a desktop browser.
-    "chrome://extension-icon/",
-    "chrome://resources/",
-    "chrome://theme/",
-    "clipboardWrite",
-    "clipboardRead",
     "power",
-    "https://docs.google.com/",
-    "https://*.googleusercontent.com/",
-    "https://drive.google.com/"
+    "storage",
+    "unlimitedStorage",
+    "webview"
   ],
   "file_browser_handlers": [
     {