bluetooth: Add option dict to ReadValue/WriteValue dbus call

device/bluetooth/dbus/bluetooth_gatt_characteristic_client.cc

 // Copyright 2014 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/dbus/bluetooth_gatt_characteristic_client.h"
 
 #include <stddef.h>
 
 #include "base/bind.h"
 #include "base/macros.h"
@@ skipping 77 matching lines @@
         object_manager_->GetObjectProxy(object_path);
     if (!object_proxy) {
       error_callback.Run(kUnknownCharacteristicError, "");
       return;
     }
 
     dbus::MethodCall method_call(
         bluetooth_gatt_characteristic::kBluetoothGattCharacteristicInterface,
         bluetooth_gatt_characteristic::kReadValue);
 
+    // Append empty option dict

[ortuno, 2016/05/27 20:16:53]

Any reason why you do this manually instead of using the AppendValueData[1]
helper function? If not I suggest using the helper function.

[1]
https://code.google.com/p/chromium/codesearch#chromium/src/dbus/values_util.h...

+    dbus::MessageWriter writer(&method_call);
+    dbus::MessageWriter array_writer(NULL);
+    writer.OpenArray("{sv}", &array_writer);
+    writer.CloseContainer(&array_writer);
+
     object_proxy->CallMethodWithErrorCallback(
         &method_call, dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
         base::Bind(&BluetoothGattCharacteristicClientImpl::OnValueSuccess,
                    weak_ptr_factory_.GetWeakPtr(), callback),
         base::Bind(&BluetoothGattCharacteristicClientImpl::OnError,
                    weak_ptr_factory_.GetWeakPtr(), error_callback));
   }
 
   // BluetoothGattCharacteristicClient override.
   void WriteValue(const dbus::ObjectPath& object_path,
                   const std::vector<uint8_t>& value,
                   const base::Closure& callback,
                   const ErrorCallback& error_callback) override {
     dbus::ObjectProxy* object_proxy =
         object_manager_->GetObjectProxy(object_path);
     if (!object_proxy) {
       error_callback.Run(kUnknownCharacteristicError, "");
       return;
     }
 
     dbus::MethodCall method_call(
         bluetooth_gatt_characteristic::kBluetoothGattCharacteristicInterface,
         bluetooth_gatt_characteristic::kWriteValue);
     dbus::MessageWriter writer(&method_call);
     writer.AppendArrayOfBytes(value.data(), value.size());
 
+    // Append empty option dict
+    dbus::MessageWriter array_writer(NULL);
+    writer.OpenArray("{sv}", &array_writer);
+    writer.CloseContainer(&array_writer);
+
     object_proxy->CallMethodWithErrorCallback(
         &method_call, dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
         base::Bind(&BluetoothGattCharacteristicClientImpl::OnSuccess,
                    weak_ptr_factory_.GetWeakPtr(), callback),
         base::Bind(&BluetoothGattCharacteristicClientImpl::OnError,
                    weak_ptr_factory_.GetWeakPtr(), error_callback));
   }
 
   // BluetoothGattCharacteristicClient override.
   void StartNotify(const dbus::ObjectPath& object_path,
@@ skipping 154 matching lines @@
 BluetoothGattCharacteristicClient::BluetoothGattCharacteristicClient() {}
 
 BluetoothGattCharacteristicClient::~BluetoothGattCharacteristicClient() {}
 
 // static
 BluetoothGattCharacteristicClient* BluetoothGattCharacteristicClient::Create() {
   return new BluetoothGattCharacteristicClientImpl();
 }
 
 }  // namespace bluez