Remove usage of FOR_EACH_OBSERVER macro in device/

device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc

Index: device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc
diff --git a/device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc b/device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc
index 4123e2d342dbaaca59093d62c1ff4ac8538de20e..54726ae7335b4807f49ad4acbd398dd2a3e99950 100644
--- a/device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc
+++ b/device/bluetooth/test/mock_bluetooth_gatt_notify_session.cc
@@ -40,9 +40,8 @@ void MockBluetoothGattNotifySession::DoNotify(
     MockBluetoothAdapter* adapter,
     MockBluetoothGattCharacteristic* characteristic,
     const std::vector<uint8_t>& value) {
-  FOR_EACH_OBSERVER(
-      BluetoothAdapter::Observer, adapter->GetObservers(),
-      GattCharacteristicValueChanged(adapter, characteristic, value));
+  for (auto& observer : adapter->GetObservers())
+    observer.GattCharacteristicValueChanged(adapter, characteristic, value);
 }
 
 }  // namespace device