bluetooth: Make public BluetoothDevice::GetName method.

device/bluetooth/bluetooth_classic_device_mac.mm

Index: device/bluetooth/bluetooth_classic_device_mac.mm
diff --git a/device/bluetooth/bluetooth_classic_device_mac.mm b/device/bluetooth/bluetooth_classic_device_mac.mm
index d14f2703c98ed2b8b4ca45cf78a5044726947094..eaeba2c6bc9406628770a6edf9bf7e6da2f1df17 100644
--- a/device/bluetooth/bluetooth_classic_device_mac.mm
+++ b/device/bluetooth/bluetooth_classic_device_mac.mm
@@ -71,10 +71,6 @@ uint32_t BluetoothClassicDeviceMac::GetBluetoothClass() const {
   return [device_ classOfDevice];
 }
 
-std::string BluetoothClassicDeviceMac::GetDeviceName() const {
-  return base::SysNSStringToUTF8([device_ name]);
-}
-
 void BluetoothClassicDeviceMac::CreateGattConnectionImpl() {
   // Classic devices do not support GATT connection.
   DidFailToConnectGatt(ERROR_UNSUPPORTED_DEVICE);
@@ -110,6 +106,12 @@ uint16_t BluetoothClassicDeviceMac::GetAppearance() const {
   return 0;
 }
 
+base::Optional<std::string> BluetoothClassicDeviceMac::GetName() const {
+  if ([device_ name])
+    return base::SysNSStringToUTF8([device_ name]);
+  return base::nullopt;
+}
+
 bool BluetoothClassicDeviceMac::IsPaired() const {
   return [device_ isPaired];
 }