Add ArrayTraits<CArray<T>> utility template

ui/events/mojo/latency_info_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 UI_EVENTS_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_
 #define UI_EVENTS_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_
 
 #include "ui/events/latency_info.h"
 #include "ui/events/mojo/latency_info.mojom.h"
 #include "ui/gfx/geometry/mojo/geometry_struct_traits.h"
 
 namespace mojo {
 
-// A buffer used to read bytes directly from LatencyInfoDataView into
-// ui::LatencyInfo's input_coordinates_.
-struct InputCoordinateArray {
-  size_t size;
-  gfx::PointF* data;
-};
-
-// TODO(fsamuel): We should add a common ArrayTraits<CArray<T>> utility struct.
-template <>
-struct ArrayTraits<InputCoordinateArray> {
-  using Element = gfx::PointF;
-  static size_t GetSize(const InputCoordinateArray& b);
-  static Element* GetData(InputCoordinateArray& b);
-  static const Element* GetData(const InputCoordinateArray& b);
-  static Element& GetAt(InputCoordinateArray& b, size_t i);
-  static const Element& GetAt(const InputCoordinateArray& b, size_t i);
-  static bool Resize(InputCoordinateArray& b, size_t size);
-};
+using InputCoordinateArray = CArray<gfx::PointF>;
 
 template <>
 struct StructTraits<ui::mojom::LatencyComponent,
                     ui::LatencyInfo::LatencyComponent> {
   static int64_t sequence_number(
       const ui::LatencyInfo::LatencyComponent& component);
   static base::TimeTicks event_time(
       const ui::LatencyInfo::LatencyComponent& component);
   static uint32_t event_count(
       const ui::LatencyInfo::LatencyComponent& component);
@@ skipping 23 matching lines @@
   static InputCoordinateArray input_coordinates(const ui::LatencyInfo& info);
   static int64_t trace_id(const ui::LatencyInfo& info);
   static bool coalesced(const ui::LatencyInfo& info);
   static bool terminated(const ui::LatencyInfo& info);
   static bool Read(ui::mojom::LatencyInfoDataView data, ui::LatencyInfo* out);
 };
 
 }  // namespace mojo
 
 #endif  // UI_EVENTS_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_