Turn the utility process image decoder into a Mojo service.

services/image_decoder/public/interfaces/image_decoder.mojom

Index: services/image_decoder/public/interfaces/image_decoder.mojom
diff --git a/services/image_decoder/public/interfaces/image_decoder.mojom b/services/image_decoder/public/interfaces/image_decoder.mojom
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index 0000000000000000000000000000000000000000..5115fe90e557a68f480e6c4f44dfa97a2440f12a
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+// 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.
+
+module services.image_decoder;
+
+import "skia/public/interfaces/image.mojom";
+
+enum ImageCodec {
+  DEFAULT,
+  ROBUST_JPEG,
+};
+
+interface ImageDecoder {
+  DecodeImage(array<uint8> encoded_data, ImageCodec codec, bool shrink_to_fit)
+      => (bool success, skia.Image? decoded_image);
+};