Convert utility process extension Unpacker IPC to mojo

extensions/common/extension_utility_types.h

+// 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.
+
+#ifndef EXTENSIONS_COMMON_EXTENSION_UTILITY_TYPES_H_
+#define EXTENSIONS_COMMON_EXTENSION_UTILITY_TYPES_H_
+
+#include <tuple>
+#include <vector>
+
+#include "ui/gfx/ipc/skia/gfx_skia_param_traits.h"
+
+class SkBitmap;
+
+namespace base {
+class FilePath;
+}
+
+namespace extensions {
+
+using DecodedImages = std::vector<std::tuple<SkBitmap, base::FilePath>>;
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_COMMON_EXTENSION_UTILITY_TYPES_H_