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

LayoutTests/bluetooth/resources/bluetooth-helpers.js

Index: LayoutTests/bluetooth/resources/bluetooth-helpers.js
diff --git a/LayoutTests/bluetooth/resources/bluetooth-helpers.js b/LayoutTests/bluetooth/resources/bluetooth-helpers.js
index 064880493c829a79d49516cd89c63e9b8beff53e..8389adaf01a0e3d7544e7944a5eef40a5019e597 100644
--- a/LayoutTests/bluetooth/resources/bluetooth-helpers.js
+++ b/LayoutTests/bluetooth/resources/bluetooth-helpers.js
@@ -85,3 +85,24 @@ function assert_promise_rejects_with_message(promise, expected, description) {
     }
   });
 }
+
+// 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);
+  }
+}