Reland: Split the code for fetching images and for decoding images into two separate classes. This w

chrome/browser/search/suggestions/image_decoder_impl.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_SEARCH_SUGGESTIONS_IMAGE_DECODER_IMPL_H_
+#define CHROME_BROWSER_SEARCH_SUGGESTIONS_IMAGE_DECODER_IMPL_H_
+
+#include <memory>
+#include <vector>
+
+#include "chrome/browser/image_decoder.h"
+#include "components/image_fetcher/image_decoder.h"
+
+class SkBitmap;
+
+namespace suggestions {
+
+// image_fetcher::ImageDecoder Implementation.
+class ImageDecoderImpl : public image_fetcher::ImageDecoder {
+ public:
+  ImageDecoderImpl();
+  ~ImageDecoderImpl() override;
+
+  void DecodeImage(
+      const std::string& image_data,
+      const image_fetcher::ImageDecodedCallback& callback) override;
+
+ private:
+  class DecodeImageRequest;
+
+  // Removes the passed image decode |request| from the internal request queue.
+  void RemoveDecodeImageRequest(DecodeImageRequest* request);
+
+  // All active image decoding requests.
+  std::vector<std::unique_ptr<DecodeImageRequest>> decode_image_requests_;
+
+  DISALLOW_COPY_AND_ASSIGN(ImageDecoderImpl);
+};
+
+}  // namespace suggestions
+
+#endif  // CHROME_BROWSER_SEARCH_SUGGESTIONS_IMAGE_DECODER_IMPL_H_
+