Turn the utility process image decoder into a Mojo service.

services/image_decoder/public/interfaces/image_decoder.mojom

+// 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;
+
+import "skia/public/interfaces/bitmap.mojom";

[sky, 2015/04/01 15:00:45]

Have you considered nuking the public part of the path, eg
ervices/image_decoder/public/interfaces. 'public' is helpful in the mojo repo as
parts of it are exported, but I don't think that applies to the chrome repo. I
would be inclined to make this path: services/image_decoder/interfaces. If we do
want private interfaces I would make that the special case, eg
ervices/image_decoder/private/interfaces.

[Anand Mistry (off Chromium), 2015/04/02 04:29:45]

A couple of thoughts about this:
1. These interfaces are public. There are other public things as well, such as
type converters, and maybe helper functions or simple wrappers. I think it makes
sense to keep these together.
2. This is kinda modeled after content/ which explicitly calls out public
things, and keeps private things implicit.

[sky, 2015/04/02 17:20:10]

Fair enough.

+
+enum ImageCodec {
+  DEFAULT,
+  ROBUST_JPEG,
+};
+
+interface ImageDecoder {
+  DecodeImage(array<uint8> encoded_data, ImageCodec codec, bool shrink_to_fit)
+      => (bool success, skia.Bitmap? decoded_image);
+};