cheets: implement cros side of WallpaperManagerService.

chrome/browser/chromeos/arc/arc_wallpaper_service.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 CHROME_BROWSER_CHROMEOS_ARC_ARC_WALLPAPER_SERVICE_H_
+#define CHROME_BROWSER_CHROMEOS_ARC_ARC_WALLPAPER_SERVICE_H_
+
+#include <stdint.h>
+
+#include <memory>
+#include <set>
+#include <vector>
+
+#include "base/macros.h"
+#include "chrome/browser/image_decoder.h"
+#include "components/arc/arc_service.h"
+#include "components/arc/common/wallpaper.mojom.h"
+#include "components/arc/instance_holder.h"
+#include "components/arc/set_wallpaper_delegate.h"
+#include "mojo/public/cpp/bindings/binding.h"
+
+class SkBitmap;
+
+namespace arc {
+
+// Lives on the UI thread.
+class ArcWallpaperService
+    : public ArcService,
+      public SetWallpaperDelegate,
+      public ImageDecoder::ImageRequest,
+      public InstanceHolder<mojom::WallpaperInstance>::Observer,
+      public mojom::WallpaperHost {
+ public:
+  explicit ArcWallpaperService(ArcBridgeService* bridge_service);
+  ~ArcWallpaperService() override;
+
+  // InstanceHolder<mojom::WallpaperInstance>::Observer overrides.
+  void OnInstanceReady() override;
+
+  // mojom::WallpaperHost overrides.
+  // TODO(muyuanli): change callback prototype when use_new_wrapper_types is
+  // updated and merge them with the functions below.
+  void SetWallpaper(mojo::Array<uint8_t> png_data) override;
+  void GetWallpaper(
+      const base::Callback<void(mojo::Array<uint8_t>)>& callback) override;

[hidehiko, 2016/09/07 01:16:25]

could you use "const GetWallpaperCallback&"?

+
+  // SetWallpaperDelegate implementation.
+  void SetWallpaperJPEG(const std::vector<uint8_t>& jpeg_data) override;
+  // ImageDecoder::ImageRequest implementation.
+  void OnImageDecoded(const SkBitmap& bitmap) override;
+  void OnDecodeImageFailed() override;
+
+ private:
+  mojo::Binding<mojom::WallpaperHost> binding_;
+  DISALLOW_COPY_AND_ASSIGN(ArcWallpaperService);
+};
+
+}  // namespace arc
+
+#endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_WALLPAPER_SERVICE_H_