Add DBus plumbing and tests for sending devices with ATT read/writes.

device/bluetooth/dbus/bluetooth_gatt_attribute_value_delegate.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_DBUS_BLUETOOTH_GATT_ATTRIBUTE_VALUE_DELEGATE_H_
 #define DEVICE_BLUETOOTH_DBUS_BLUETOOTH_GATT_ATTRIBUTE_VALUE_DELEGATE_H_
 
 #include <cstdint>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "device/bluetooth/bluetooth_local_gatt_service.h"
 
+namespace dbus {
+class ObjectPath;
+}
+
+namespace device {
+class BluetoothDevice;
+}
+
 namespace bluez {
 
+class BluetoothLocalGattServiceBlueZ;
+
 // A simpler interface for reacting to GATT attribute value requests by the
 // DBus attribute service providers.
 class BluetoothGattAttributeValueDelegate {
  public:
-  virtual ~BluetoothGattAttributeValueDelegate() {}
+  explicit BluetoothGattAttributeValueDelegate(
+      BluetoothLocalGattServiceBlueZ* service);
+  virtual ~BluetoothGattAttributeValueDelegate();
 
   // This method will be called when a remote device requests to read the
   // value of the exported GATT attribute. Invoke |callback| with a value
   // to return that value to the requester. Invoke |error_callback| to report
   // a failure to read the value. This can happen, for example, if the
   // attribute has no read permission set. Either callback should be
   // invoked after a reasonable amount of time, since the request will time
   // out if left pending for too long causing a disconnection.
   virtual void GetValue(
+      const dbus::ObjectPath& device_path,
       const device::BluetoothLocalGattService::Delegate::ValueCallback&
           callback,
       const device::BluetoothLocalGattService::Delegate::ErrorCallback&
           error_callback) = 0;
 
   // This method will be called, when a remote device requests to write the
   // value of the exported GATT attribute. Invoke |callback| to report
   // that the value was successfully written. Invoke |error_callback| to
   // report a failure to write the value. This can happen, for example, if the
   // attribute has no write permission set. Either callback should be
   // invoked after a reasonable amount of time, since the request will time
   // out if left pending for too long causing a disconnection.
   virtual void SetValue(
+      const dbus::ObjectPath& device_path,
       const std::vector<uint8_t>& value,
       const base::Closure& callback,
       const device::BluetoothLocalGattService::Delegate::ErrorCallback&
           error_callback) = 0;
 
   // This method will be called, when a remote device requests to start sending
   // notifications for this characteristic. This will never be called for
   // descriptors.
   virtual void StartNotifications() = 0;
 
   // This method will be called, when a remote device requests to stop sending
   // notifications for this characteristic. This will never be called for
   // descriptors.
   virtual void StopNotifications() = 0;
+
+ protected:
+  // Gets the Bluetooth device object on the current service's adapter with
+  // the given object path.
+  device::BluetoothDevice* GetDeviceWithPath(
+      const dbus::ObjectPath& object_path);
+
+  const BluetoothLocalGattServiceBlueZ* service() { return service_; }
+
+ private:
+  const BluetoothLocalGattServiceBlueZ* service_;
+
+  DISALLOW_COPY_AND_ASSIGN(BluetoothGattAttributeValueDelegate);
 };
 
 }  // namespace bluez
 
 #endif  // DEVICE_BLUETOOTH_DBUS_BLUETOOTH_GATT_ATTRIBUTE_VALUE_DELEGATE_H_