Implement WebBluetooth getDescriptor[s]

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

+// TODO(672127) Use this test case to test the rest of characteristic functions.
+'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 => {
+      return setBluetoothFakeAdapter('MissingServiceHeartRateAdapter')
+        .then(() => assert_promise_rejects_with_message(
+          characteristic.CALLS([
+            getDescriptor(user_description.name)|
+            getDescriptors(user_description.name)[UUID]|
+            getDescriptors(user_description.name)]),
+          new DOMException('GATT Service no longer exists.',
+                           'InvalidStateError')));
+      })
+}, 'Service is removed. Reject with InvalidStateError.');