Migrate ArcBitmap to use typemapping

components/arc/bitmap/bitmap_struct_traits.cc

+// 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 "components/arc/bitmap/bitmap_struct_traits.h"
+
+namespace mojo {
+
+bool StructTraits<arc::mojom::ArcBitmapDataView, SkBitmap>::
+    Read(arc::mojom::ArcBitmapDataView data, SkBitmap* out) {
+  mojo::ArrayDataView<uint8_t> pixel_data;
+  data.GetPixelDataDataView(&pixel_data);
+
+  SkImageInfo info = SkImageInfo::Make(
+      data.width(), data.height(),
+      kRGBA_8888_SkColorType, kPremul_SkAlphaType);
+  if (info.getSafeSize(info.minRowBytes()) > pixel_data.size()) {
+    // Insufficient buffer size.
+    return false;
+  }
+
+  // Create the SkBitmap object which wraps the arc bitmap pixels. This
+  // doesn't copy and |data| and |bitmap| share the buffer.
+  SkBitmap bitmap;
+  if (!bitmap.installPixels(info,
+          const_cast<uint8_t*>(pixel_data.data()),
+          info.minRowBytes())) {
+    // Error in installing pixels.
+    return false;
+  }
+
+  // Copy the pixels with converting color type.
+  if (!bitmap.copyTo(out, kN32_SkColorType)) {

[dcheng, 2016/09/13 23:39:16]

return bitmap.CopyTo(...);

+    // Error in copying or converting the color type.
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace mojo