Implement the gattserverdisconnected event.

third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js

Index: third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js
diff --git a/third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js b/third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js
index 6735a3b04e706217177533717911ac0baa13a87d..2bc9c03ed730dd5c27718401b448d64945095bab 100644
--- a/third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js
+++ b/third_party/WebKit/LayoutTests/resources/bluetooth/bluetooth-helpers.js
@@ -3,6 +3,7 @@
 // Bluetooth UUID constants:
 // Services:
 var blacklist_test_service_uuid = "611c954a-263b-4f4a-aab6-01ddb953f985";
+var request_disconnection_service_uuid = "01d7d889-7451-419f-aeb8-d65e7b9277af";
 // Characteristics:
 var blacklist_exclude_reads_characteristic_uuid =
   "bad1c9a2-9a5b-4015-8b60-1579bbbf2135";
@@ -216,6 +217,16 @@ function runGarbageCollection()
       });
 }
 
+function eventPromise(target, type, options) {
+  return new Promise(resolve => {
+    let wrapper = function(event) {
+      target.removeEventListener(type, wrapper);
+      resolve(event);
+    };
+    target.addEventListener(type, wrapper, options);
+  });
+}
+
 // Creates |num_listeners| promises. Each adds an event listener
 // to object. The promises resolve once the object fires |event| but
 // reject if the event is fired before |object|.|func|() resolves.