bluetooth: Create Mojo equivalent of SetBluetoothMockDataSet

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

Index: third_party/WebKit/LayoutTests/bluetooth/resources/bluetooth-helpers.js
diff --git a/third_party/WebKit/LayoutTests/bluetooth/resources/bluetooth-helpers.js b/third_party/WebKit/LayoutTests/bluetooth/resources/bluetooth-helpers.js
index a6f9310c828e78020a41e9ec14b2ea6184242e0d..5b61367927720760a60038b03d9733088b3915ba 100644
--- a/third_party/WebKit/LayoutTests/bluetooth/resources/bluetooth-helpers.js
+++ b/third_party/WebKit/LayoutTests/bluetooth/resources/bluetooth-helpers.js
@@ -150,6 +150,12 @@ function getBluetoothManualChooserEvents(expected_count) {
   });
 }
 
+function setBluetoothFakeAdapter(adapter_name) {
+  return new Promise(resolve => {
+    testRunner.setBluetoothFakeAdapter(adapter_name, resolve);
+  });
+}
+
 // errorUUID(alias) returns a UUID with the top 32 bits of
 // '00000000-97e5-4cd7-b9f1-f5a427670c59' replaced with the bits of |alias|.
 // For example, errorUUID(0xDEADBEEF) returns