bluetooth: Shutdown BluetoothAdapter before DBus on ChromeOS.

device/bluetooth/bluetooth_adapter_factory.h

Index: device/bluetooth/bluetooth_adapter_factory.h
diff --git a/device/bluetooth/bluetooth_adapter_factory.h b/device/bluetooth/bluetooth_adapter_factory.h
index 9b98a211559aeb80604f58179f420427665985f0..6043e4a0cbaee9eb84585f19e72c8215a61771bf 100644
--- a/device/bluetooth/bluetooth_adapter_factory.h
+++ b/device/bluetooth/bluetooth_adapter_factory.h
@@ -29,6 +29,11 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothAdapterFactory {
   // use.
   static void GetAdapter(const AdapterCallback& callback);
 
+#if defined(OS_CHROMEOS)
+  // Calls |BluetoothAdapterChromeOS::OnDBusThreadManagerShutdown|.
+  static void OnDBusThreadManagerShutdown();
+#endif
+
   // Sets the shared instance of the default adapter for testing purposes only,
   // no reference is retained after completion of the call, removing the last
   // reference will reset the factory.