Add ArrayTraits<CArray<T>> utility template

skia/public/interfaces/bitmap_skbitmap_struct_traits.h

 // 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.
 
 #ifndef SKIA_PUBLIC_INTERFACES_BITMAP_SKBITMAP_STRUCT_TRAITS_H_
 #define SKIA_PUBLIC_INTERFACES_BITMAP_SKBITMAP_STRUCT_TRAITS_H_
 
 #include "mojo/public/cpp/bindings/array_traits.h"
 #include "skia/public/interfaces/bitmap.mojom.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
 namespace mojo {
 
 // A buffer used to read pixel data directly from BitmapDataView to SkBitmap.
-struct BitmapBuffer {
-  uint8_t* data = nullptr;
-  size_t size = 0;
-};
-
-// ArrayTraits needed for ReadPixelData use with BitmapBuffer.
-template <>
-struct ArrayTraits<BitmapBuffer> {
-  using Element = uint8_t;
-  static size_t GetSize(const BitmapBuffer& b);
-  static uint8_t* GetData(BitmapBuffer& b);
-  static const uint8_t* GetData(const BitmapBuffer& b);
-  static uint8_t& GetAt(BitmapBuffer& b, size_t i);
-  static const uint8_t& GetAt(const BitmapBuffer& b, size_t i);
-  static bool Resize(BitmapBuffer& b, size_t size);
-};
+using BitmapBuffer = CArray<uint8_t>;
 
 // Struct traits to use SkBitmap for skia::mojom::Bitmap in Chrome C++ code.
 template <>
 struct StructTraits<skia::mojom::Bitmap, SkBitmap> {
   static bool IsNull(const SkBitmap& b);
   static void SetToNull(SkBitmap* b);
   static skia::mojom::ColorType color_type(const SkBitmap& b);
   static skia::mojom::AlphaType alpha_type(const SkBitmap& b);
   static skia::mojom::ColorProfileType profile_type(const SkBitmap& b);
   static uint32_t width(const SkBitmap& b);
   static uint32_t height(const SkBitmap& b);
   static BitmapBuffer pixel_data(const SkBitmap& b);
   static bool Read(skia::mojom::BitmapDataView data, SkBitmap* b);
   static void* SetUpContext(const SkBitmap& b);
   static void TearDownContext(const SkBitmap& b, void* context);
 };
 
 }  // namespace mojo
 
 #endif  // SKIA_PUBLIC_INTERFACES_BITMAP_SKBITMAP_STRUCT_TRAITS_H_