Add LoadComponent API in ImageLoader dbus adapter.

chromeos/dbus/fake_image_loader_client.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 CHROMEOS_DBUS_FAKE_IMAGE_LOADER_CLIENT_H_
 #define CHROMEOS_DBUS_FAKE_IMAGE_LOADER_CLIENT_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "chromeos/dbus/image_loader_client.h"
 
 namespace chromeos {
 
 // A fake implementation of ImageLoaderClient. This class does nothing.
 class CHROMEOS_EXPORT FakeImageLoaderClient : public ImageLoaderClient {
  public:
   FakeImageLoaderClient() {}
   ~FakeImageLoaderClient() override {}
 
   // DBusClient ovveride.
   void Init(dbus::Bus* dbus) override {}
 
   // ImageLoaderClient override:
   void RegisterComponent(const std::string& name,
                          const std::string& version,
                          const std::string& component_folder_abs_path,
                          const BoolDBusMethodCallback& callback) override;
+  void LoadComponent(const std::string& name,
+                     const StringDBusMethodCallback& callback) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(FakeImageLoaderClient);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_DBUS_FAKE_IMAGE_LOADER_CLIENT_H_