bluetooth: mac: Initial BluetoothRemoteGattCharacteristicMac implementation

device/bluetooth/test/mock_bluetooth_cbservice_mac.h

 // 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.
 
 #ifndef DEVICE_BLUETOOTH_TEST_MOCK_BLUETOOTH_CBSERVICE_MAC_H_
 #define DEVICE_BLUETOOTH_TEST_MOCK_BLUETOOTH_CBSERVICE_MAC_H_
 
 #include "base/mac/sdk_forward_declarations.h"
 #include "build/build_config.h"
 
 #import <CoreBluetooth/CoreBluetooth.h>
 
 // This class mocks the behavior of a CBService.
 @interface MockCBService : NSObject
 
 @property(readonly, nonatomic) CBUUID* UUID;
 @property(readonly, nonatomic) BOOL isPrimary;
 @property(readonly, nonatomic) CBService* service;
 
-- (instancetype)initWithCBUUID:(CBUUID*)uuid primary:(BOOL)isPrimary;
+- (instancetype)initWithPeripheral:(CBPeripheral*)peripheral
+                            CBUUID:(CBUUID*)uuid
+                           primary:(BOOL)isPrimary;
+
+// Creates and adds a mock characteristic.
+- (void)addCharacteristicWithUUID:(CBUUID*)cb_uuid properties:(int)properties;
 
 @end
 
 #endif  // DEVICE_BLUETOOTH_TEST_MOCK_BLUETOOTH_CBSERVICE_MAC_H_