bluetooth: Make public BluetoothDevice::GetName method.

device/bluetooth/bluetooth_low_energy_win.h

Index: device/bluetooth/bluetooth_low_energy_win.h
diff --git a/device/bluetooth/bluetooth_low_energy_win.h b/device/bluetooth/bluetooth_low_energy_win.h
index 65120a28265aa65ef59224bf185b8360957e1d16..edb17e933caa729b14afed0458d59cf649bd9a25 100644
--- a/device/bluetooth/bluetooth_low_energy_win.h
+++ b/device/bluetooth/bluetooth_low_energy_win.h
@@ -13,6 +13,7 @@
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
+#include "base/optional.h"
 #include "device/bluetooth/bluetooth_export.h"
 #include "device/bluetooth/bluetooth_low_energy_defs_win.h"
 
@@ -88,7 +89,7 @@ struct DEVICE_BLUETOOTH_EXPORT BluetoothLowEnergyDeviceInfo {
 
   base::FilePath path;
   std::string id;
-  std::string friendly_name;
+  base::Optional<std::string> friendly_name;
   BLUETOOTH_ADDRESS address;
   bool visible;
   bool authenticated;