Add ios_image_decoder_impl.*

ios/chrome/browser/suggestions/ios_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 IOS_CHROME_BROWSER_SUGGESTIONS_IOS_IMAGE_DECODER_IMPL_H_
+#define IOS_CHROME_BROWSER_SUGGESTIONS_IOS_IMAGE_DECODER_IMPL_H_
+
+#include "base/macros.h"
+#include "components/image_fetcher/image_decoder.h"
+
+namespace suggestions {
+
+class IOSImageDecoderImpl : public image_fetcher::ImageDecoder {
+ public:
+  IOSImageDecoderImpl();
+  ~IOSImageDecoderImpl() override;
+
+  void DecodeImage(
+      const std::string& image_data,

[noyau (Ping after 24h), 2016/06/30 08:28:53]

I'm just curious why this api uses a string here and not simply a vector/array
of bytes?

[markusheintz_, 2016/06/30 09:15:14]

I want to get rid of the std::string as byte buffer. This is on the TODO list in
my head. I filed a bug for this to track the work
(https://bugs.chromium.org/p/chromium/issues/detail?id=624720)

Three reasons why I have not does this yet:
1) The URL Fetcher returns the response as string so this was the common
denominator to start with (see
https://cs.chromium.org/chromium/src/components/image_fetcher/image_data_fetc...)
2) This work was blocking other so I needed to move.
3) I have not compared the different options yet. I first wanted to see how many
different byte buffers or options already exist in the Chrome code base before I
add mine ;-)

+      const image_fetcher::ImageDecodedCallback& callback) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(IOSImageDecoderImpl);
+};
+
+}  // namespace suggestions
+
+#endif  // IOS_CHROME_BROWSER_SUGGESTIONS_IOS_IMAGE_DECODER_IMPL_H_