Remove usage of FOR_EACH_OBSERVER macro in device/

device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc

Index: device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc
diff --git a/device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc b/device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc
index b32befc80083f5f6bb406b81c17debac73535d6f..92dd12a03793b1d012d7ba27841549a7eac4b991 100644
--- a/device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc
+++ b/device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_client.cc
@@ -196,20 +196,20 @@ void FakeBluetoothGattDescriptorClient::OnPropertyChanged(
   VLOG(2) << "Descriptor property changed: " << object_path.value() << ": "
           << property_name;
 
-  FOR_EACH_OBSERVER(BluetoothGattDescriptorClient::Observer, observers_,
-                    GattDescriptorPropertyChanged(object_path, property_name));
+  for (auto& observer : observers_)
+    observer.GattDescriptorPropertyChanged(object_path, property_name);
 }
 
 void FakeBluetoothGattDescriptorClient::NotifyDescriptorAdded(
     const dbus::ObjectPath& object_path) {
-  FOR_EACH_OBSERVER(BluetoothGattDescriptorClient::Observer, observers_,
-                    GattDescriptorAdded(object_path));
+  for (auto& observer : observers_)
+    observer.GattDescriptorAdded(object_path);
 }
 
 void FakeBluetoothGattDescriptorClient::NotifyDescriptorRemoved(
     const dbus::ObjectPath& object_path) {
-  FOR_EACH_OBSERVER(BluetoothGattDescriptorClient::Observer, observers_,
-                    GattDescriptorRemoved(object_path));
+  for (auto& observer : observers_)
+    observer.GattDescriptorRemoved(object_path);
 }
 
 }  // namespace bluez