Add listener for AdapterDiscoveringChanged on BT chooser-controller

content/browser/bluetooth/web_bluetooth_service_impl.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // ID Not In Map Note:
 // A service, characteristic, or descriptor ID not in the corresponding
 // WebBluetoothServiceImpl map [service_id_to_device_address_,
 // characteristic_id_to_service_id_, descriptor_to_characteristic_] implies a
 // hostile renderer because a renderer obtains the corresponding ID from this
 // class and it will be added to the map at that time.
@@ skipping 212 matching lines @@
 
 void WebBluetoothServiceImpl::AdapterPoweredChanged(
     device::BluetoothAdapter* adapter,
     bool powered) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   if (device_chooser_controller_.get()) {
     device_chooser_controller_->AdapterPoweredChanged(powered);
   }
 }
 
+void WebBluetoothServiceImpl::AdapterDiscoveringChanged(
+    device::BluetoothAdapter* adapter,
+    bool discovering) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  if (device_chooser_controller_.get()) {
+    device_chooser_controller_->AdapterDiscoveringChanged(discovering);
+  }
+}
+
 void WebBluetoothServiceImpl::DeviceAdded(device::BluetoothAdapter* adapter,
                                           device::BluetoothDevice* device) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   if (device_chooser_controller_.get()) {
     device_chooser_controller_->AddFilteredDevice(*device);
   }
 }
 
 void WebBluetoothServiceImpl::DeviceChanged(device::BluetoothAdapter* adapter,
                                             device::BluetoothDevice* device) {
@@ skipping 757 matching lines @@
   characteristic_id_to_service_id_.clear();
   service_id_to_device_address_.clear();
   connected_devices_.reset(
       new FrameConnectedBluetoothDevices(render_frame_host_));
   allowed_devices_map_ = BluetoothAllowedDevicesMap();
   device_chooser_controller_.reset();
   BluetoothAdapterFactoryWrapper::Get().ReleaseAdapter(this);
 }
 
 }  // namespace content