Adding the last test related with connect/disconnect

device/bluetooth/bluetooth_low_energy_device_mac.mm

 // Copyright 2015 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.
 
 #include "device/bluetooth/bluetooth_low_energy_device_mac.h"
 
 #import <CoreFoundation/CoreFoundation.h>
 #include <stddef.h>
 
 #include "base/mac/mac_util.h"
@@ skipping 251 matching lines @@
 }
 
 device::BluetoothAdapterMac* BluetoothLowEnergyDeviceMac::GetMacAdapter() {
   return static_cast<BluetoothAdapterMac*>(this->adapter_);
 }
 
 CBPeripheral* BluetoothLowEnergyDeviceMac::GetPeripheral() {
   return peripheral_;
 }
 
-void BluetoothLowEnergyDeviceMac::DidDisconnectPeripheral() {
+void BluetoothLowEnergyDeviceMac::DidDisconnectPeripheral(
+    BluetoothDevice::ConnectErrorCode error_code) {
   if (create_gatt_connection_error_callbacks_.empty()) {
+    // TODO(http://crbug.com/585897): Need to pass the error.
     DidDisconnectGatt();
   } else {
-    DidFailToConnectGatt(ERROR_FAILED);
+    DidFailToConnectGatt(error_code);
   }
 }