Implement WebBluetooth descriptor.readValue()

third_party/WebKit/LayoutTests/bluetooth/script-tests/descriptor/descriptor-is-removed.js

+'use strict';
+promise_test(() => {
+  return setBluetoothFakeAdapter('DisconnectingHealthThermometerAdapter')
+      .then(
+          () => requestDeviceWithKeyDown(
+              {filters: [{services: ['health_thermometer']}]}))
+      .then(device => device.gatt.connect())
+      .then(gattServer => gattServer.getPrimaryService('health_thermometer'))
+      .then(service => service.getCharacteristic('measurement_interval'))
+      .then(
+          characteristic => characteristic.getDescriptor(user_description.name))
+      .then(descriptor => {
+        return setBluetoothFakeAdapter(
+                   'MissingDescriptorsDisconnectingHealthThermometerAdapter')
+            .then(
+                () => assert_promise_rejects_with_message(
+                    descriptor.CALLS([readValue()]),
+                    new DOMException(
+                        'GATT Descriptor no longer exists.',
+                        'InvalidStateError'),
+                    'Descriptor got removed.'));
+      });
+}, 'Descriptor gets removed. Reject with InvalidStateError.');