bluetooth: {start,stop}Notifications() return the characteristic

third_party/WebKit/LayoutTests/bluetooth/notifications/stop-after-start-succeeds.html

Index: third_party/WebKit/LayoutTests/bluetooth/notifications/stop-after-start-succeeds.html
diff --git a/third_party/WebKit/LayoutTests/bluetooth/notifications/start-stop-start-stop.html b/third_party/WebKit/LayoutTests/bluetooth/notifications/stop-after-start-succeeds.html
similarity index 79%
copy from third_party/WebKit/LayoutTests/bluetooth/notifications/start-stop-start-stop.html
copy to third_party/WebKit/LayoutTests/bluetooth/notifications/stop-after-start-succeeds.html
index 1e65acbfe0d335b524c6e716900e8a04bb169369..209ccf9eaaf267a71acfd74152ac583b69230fa3 100644
--- a/third_party/WebKit/LayoutTests/bluetooth/notifications/start-stop-start-stop.html
+++ b/third_party/WebKit/LayoutTests/bluetooth/notifications/stop-after-start-succeeds.html
@@ -14,10 +14,12 @@ promise_test(() => {
     .then(characteristic => {
       return characteristic.startNotifications()
         .then(() => characteristic.stopNotifications())
-        .then(() => characteristic.startNotifications())
-        .then(() => characteristic.stopNotifications());
+        .then(result => {
+          assert_equals(result, characteristic,
+	                'Result should be the same as characteristic.');

[ortuno, 2016/08/05 01:43:44]

You could do:

  .then(characteristic => {
    return characteristic.startNotifications()
      .then(start_characteristic => {
          assert_equals(start_characteristic, characteristic, ...);
          return characteristic.stopNotifications()
            .then(stop_characteristic => { 
               // assert the same as characteristic and start_characteristic
            });
       });
   });

[François Beaufort, 2016/08/05 06:41:15]

Done.

+        });
     });
   // TODO(ortuno): Assert that notifications are not active.
   // http://crbug.com/600762
-}, 'Start -> stop -> start -> stop.');
+}, 'Single stop after start notifications succeeds.');
 </script>