Replace image_messages.h with Mojo service

content/browser/image_downloader/image_downloader_dispatcher.h

+// Copyright 2015 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 CONTENT_BROWSER_IMAGE_DOWNLOADER_DISPATCHER_H_
+#define CONTENT_BROWSER_IMAGE_DOWNLOADER_DISPATCHER_H_
+
+#include "base/macros.h"
+#include "content/common/image_downloader/image_downloader.mojom.h"
+#include "content/public/browser/web_contents.h"
+
+class GURL;
+
+namespace content {
+
+class RenderFrameHost;
+
+class ImageDownloaderDispatcher : public mojo::ErrorHandler {

[Ken Rockot(use gerrit already), 2015/04/14 16:14:20]

nit: Please add a brief comment documenting the purpose of the class

[leonhsl(Using Gerrit), 2015/04/17 06:14:34]

Done.

+ public:
+  explicit ImageDownloaderDispatcher(RenderFrameHost* render_frame_host);
+  ~ImageDownloaderDispatcher() override;
+
+  int StartDownload(const GURL& url,
+                    bool is_favicon,
+                    uint32_t max_bitmap_size,
+                    bool bypass_cache,
+                    const WebContents::ImageDownloadCallback& callback);
+
+ private:
+  // Overidden from mojo::ErrorHandler:
+  void OnConnectionError() override;
+
+  static int next_image_download_id_;
+
+  RenderFrameHost* render_frame_host_;
+  image_downloader::ImageDownloaderPtr downloader_;
+
+  DISALLOW_COPY_AND_ASSIGN(ImageDownloaderDispatcher);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_IMAGE_DOWNLOADER_DISPATCHER_H_