Introduce the image_decoder service

services/image_decoder/public/cpp/decode.cc

Index: services/image_decoder/public/cpp/decode.cc
diff --git a/services/image_decoder/public/cpp/decode.cc b/services/image_decoder/public/cpp/decode.cc
new file mode 100644
index 0000000000000000000000000000000000000000..24dbd5bf83d9bb5457c9dca755738a18766a4292
--- /dev/null
+++ b/services/image_decoder/public/cpp/decode.cc
@@ -0,0 +1,49 @@
+// 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.
+
+#include "services/image_decoder/public/cpp/decode.h"
+
+#include "services/image_decoder/public/cpp/constants.h"
+#include "services/service_manager/public/cpp/connector.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+
+namespace image_decoder {
+
+namespace {
+
+// Helper callback which owns an ImageDecoderPtr until invoked. This keeps the
+// ImageDecoder pipe open just long enough to dispatch a reply, at which point
+// the reply is forwarded to the wrapped |callback|.
+void OnDecodeImage(mojom::ImageDecoderPtr decoder,
+                   const mojom::ImageDecoder::DecodeImageCallback& callback,
+                   const SkBitmap& bitmap) {
+  callback.Run(bitmap);
+}
+
+// Called in the case of a connection error on an ImageDecoder proxy.
+void OnConnectionError(
+    const mojom::ImageDecoder::DecodeImageCallback& callback) {
+  SkBitmap null_bitmap;
+  callback.Run(null_bitmap);
+}
+
+}  // namespace
+
+void Decode(service_manager::Connector* connector,
+            const std::vector<uint8_t>& encoded_bytes,
+            mojom::ImageCodec codec,
+            bool shrink_to_fit,
+            uint64_t max_size_in_bytes,
+            const mojom::ImageDecoder::DecodeImageCallback& callback) {
+  mojom::ImageDecoderPtr decoder;
+  connector->ConnectToInterface(kServiceName, &decoder);
+  decoder.set_connection_error_handler(
+      base::Bind(&OnConnectionError, callback));
+  mojom::ImageDecoder* raw_decoder = decoder.get();
+  raw_decoder->DecodeImage(
+      encoded_bytes, codec, shrink_to_fit, max_size_in_bytes,
+      base::Bind(&OnDecodeImage, base::Passed(&decoder), callback));
+}
+
+}  // namespace image_decoder