Test that the right events are sent to the Bluetooth chooser.

LayoutTests/bluetooth/resources/bluetooth-helpers.js

 'use strict';
 
 // Sometimes we need to test that using either the name, alias, or UUID
 // produces the same result. The following objects help us do that.
 var generic_access = {
   alias: 0x1800,
   name: 'generic_access',
   uuid: '00001800-0000-1000-8000-00805f9b34fb'
 };
 var device_name = {
@@ skipping 67 matching lines @@
 function assert_promise_rejects_with_message(promise, expected, description) {
   return promise.then(() => {
     assert_unreached('Promise should have rejected: ' + description);
   }, error => {
     assert_equals(error.name, expected.name, 'Unexpected Error Name:');
     if (expected.message) {
       assert_equals(error.message, expected.message, 'Unexpected Error Message:');
     }
   });
 }
+
+// Parses add-device(name)=id lines in
+// testRunner.getBluetoothManualChooserEvents() output, and exposes the name->id
+// mapping.
+class AddDeviceEventSet {
+  constructor() {
+    this._idsByName = new Map();
+    this._addDeviceRegex = /^add-device\(([^)]+)\)=(.+)$/;
+  }
+  assert_add_device_event(event, description) {
+    let match = this._addDeviceRegex.exec(event);
+    assert_true(!!match, event + "isn't an add-device event: " + description);
+    this._idsByName.set(match[1], match[2]);
+  }
+  has(name) {
+    return this._idsByName.has(name);
+  }
+  get(name) {
+    return this._idsByName.get(name);
+  }
+}