Add the feature to retain the user gesture in the extension callback

chrome/test/data/extensions/api_test/permissions/optional_retain_gesture/background.js

Index: chrome/test/data/extensions/api_test/permissions/optional_retain_gesture/background.js
===================================================================
--- chrome/test/data/extensions/api_test/permissions/optional_retain_gesture/background.js	(revision 0)
+++ chrome/test/data/extensions/api_test/permissions/optional_retain_gesture/background.js	(revision 0)
@@ -0,0 +1,78 @@
+// Copyright (c) 2014 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.
+
+var fail = chrome.test.callbackFail;
+
+var GESTURE_ERROR = "This function must be called during a user gesture";
+
+chrome.test.getConfig(function(config) {
+  chrome.test.runTests([
+    function testPermissionsRetainGesture() {
+      chrome.test.runWithUserGesture(function() {
+        chrome.permissions.request(
+            {permissions: ['bookmarks']},
+            function(granted) {
+              chrome.test.assertTrue(granted);
+
+              // The user gesture is retained, so we can request again.
+              chrome.permissions.request(
+                  {permissions: ['bookmarks']},
+                  function(granted) {
+                    // Wait 500ms for consuming the user gesture in
+                    // window.open. Can't wait longer than 1s since the user

[Marijn Kruisselbrink, 2014/04/23 23:00:43]

very minor nit: this comment is a bit misleading, since window.setTimeout is a
bit special in its user gesture treatment. window.setTimeout doesn't actually
cause the user gesture to expire, it just is not retained for timeouts > 1000ms,
which only coincidentally is the same as the time until user gestures normally
expire.

+                    // gesture will expire.
+                    window.setTimeout(function() {
+                      chrome.test.assertTrue(granted);
+                      // The user gesture is retained but is consumed outside,
+                      // so the following request will fail.
+                      chrome.permissions.request(
+                          {permissions: ['bookmarks']},
+                          fail(GESTURE_ERROR));
+                    }, 500);
+                  }
+              );
+
+              // Consume the user gesture
+              window.open("", "", "");
+            }
+        );
+      });
+    },
+
+    function testPermissionsRetainGestureExpire() {

[Marijn Kruisselbrink, 2014/04/23 23:00:43]

Similarly all the setTimeout calls in this test don't actually test what you
expect them to test. They test the fact that setTimeout doesn't retain the user
gesture when the timeout > 1000ms, but don't test that the user gesture does or
doesn't expire. (I'm not sure how you'd reliably test that anyway; the only way
to get a user gesture to expire seems to be to busy-loop for > 1 second).

+      chrome.test.runWithUserGesture(function() {
+        chrome.permissions.request(
+            {permissions: ['bookmarks']},
+            function(granted) {
+              chrome.test.assertTrue(granted);
+
+              var request = function() {
+                // The following request will fail if the user gesture is
+                // expired.
+                chrome.permissions.request(
+                    {permissions: ['bookmarks']},
+                    function(granted) {
+                      if (chrome.runtime.lastError) {
+                        chrome.test.assertFalse(granted);
+                        chrome.permissions.request(
+                            {permissions: ['bookmarks']},
+                            fail(GESTURE_ERROR));
+                      } else {
+                        console.log("Retrying permissions.request in 3 " +
+                            "seconds");
+                        window.setTimeout(request, 3000);
+                      }
+                    });
+              };
+
+              // Wait 2s since the user gesture timeout is 1s.
+              window.setTimeout(function() {
+                request();
+              }, 2000);
+            }
+        );
+      });
+    }
+  ]);
+});