cheets: remove setWallpaper from ArcIntentHelper.

components/arc/set_wallpaper_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 COMPONENTS_ARC_SET_WALLPAPER_DELEGATE_H_
-#define COMPONENTS_ARC_SET_WALLPAPER_DELEGATE_H_
-
-#include <stdint.h>
-
-#include <vector>
-
-namespace arc {
-
-// Delegate to allow setting the wallpaper.
-// TODO(muyuanli): This class will be removed once ArcIntentHelper migrates to
-// WallpaperManager API.
-class SetWallpaperDelegate {
- public:
-  virtual ~SetWallpaperDelegate() = default;
-
-  static SetWallpaperDelegate* instance() { return instance_; }
-  static void set_instance(SetWallpaperDelegate* delegate) {
-    instance_ = delegate;
-  }
-
-  // Sets an image represented in JPEG format as the wallpaper.
-  virtual void SetWallpaperJpeg(const std::vector<uint8_t>& jpeg_data) = 0;
-
- private:
-  static SetWallpaperDelegate* instance_;
-};
-
-}  // namespace arc
-
-#endif  // COMPONENTS_ARC_SET_WALLPAPER_DELEGATE_H_