Implemented StructTraits for cc::CopyOutputResult

cc/ipc/copy_output_result_struct_traits.cc

+// Copyright 2017 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 "cc/ipc/copy_output_result_struct_traits.h"
+
+namespace mojo {
+
+// static
+bool StructTraits<cc::mojom::CopyOutputResultDataView, cc::CopyOutputResult>::
+    Read(cc::mojom::CopyOutputResultDataView data, cc::CopyOutputResult* out) {
+  out->bitmap_ = base::MakeUnique<SkBitmap>();
+  return data.ReadSize(&out->size_) && data.ReadBitmap(out->bitmap_.get()) &&
+         data.ReadTextureMailbox(&out->texture_mailbox_);
+}
+
+// static
+const SkBitmap&
+StructTraits<cc::mojom::CopyOutputResultDataView, cc::CopyOutputResult>::bitmap(
+    const cc::CopyOutputResult& result) {
+  static SkBitmap* null_bitmap = nullptr;

[Ken Rockot(use gerrit already), 2017/02/01 16:04:55]

no need for this and conditional initialization. you can just

  static SkBitmap* null_bitmap = new SkBitmap;

and the right thing will happen (i.e. a new SkBitmap will be allocated exactly
once, on the first call to this function)

[Saman Sami, 2017/02/01 17:19:41]

Done.

+  if (!result.bitmap_) {
+    if (!null_bitmap)
+      null_bitmap = new SkBitmap();
+    return *null_bitmap;
+  }
+  return *result.bitmap_;
+}
+
+}  // namespace mojo