Read characteristic implementation on macOS

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 294 matching lines @@
         GetBluetoothRemoteGattService(cb_service);
     DCHECK(gatt_service);
     std::unique_ptr<BluetoothRemoteGattService> scoped_service =
         gatt_services_.take_and_erase(gatt_service->GetIdentifier());
     adapter_->NotifyGattServiceRemoved(scoped_service.get());
   }
   SetGattServicesDiscoveryComplete(false);
   [GetPeripheral() discoverServices:nil];
 }
 
+void BluetoothLowEnergyDeviceMac::DidReadValue(CBCharacteristic* characteristic,
+                                               NSError* error) {
+  BluetoothRemoteGattServiceMac* gatt_service =
+      GetBluetoothRemoteGattService(characteristic.service);
+  if (!gatt_service) {
+    return;
+  }
+  gatt_service->DidReadValue(characteristic, error);
+}
+
 // static
 std::string BluetoothLowEnergyDeviceMac::GetPeripheralIdentifier(
     CBPeripheral* peripheral) {
   DCHECK(BluetoothAdapterMac::IsLowEnergyAvailable());
   NSUUID* uuid = [peripheral identifier];
   NSString* uuidString = [uuid UUIDString];
   return base::SysNSStringToUTF8(uuidString);
 }
 
 // static
@@ skipping 37 matching lines @@
   GattServiceMap gatt_services_swapped;
   gatt_services_swapped.swap(gatt_services_);
   gatt_services_swapped.clear();
   if (create_gatt_connection_error_callbacks_.empty()) {
     // TODO(http://crbug.com/585897): Need to pass the error.
     DidDisconnectGatt();
   } else {
     DidFailToConnectGatt(error_code);
   }
 }