Remove LatencyInfo::sequence_number. (May break metrics).

ui/latency/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_LATENCY_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_
 #define UI_LATENCY_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_
 
 #include "mojo/common/common_custom_types_struct_traits.h"
 #include "ui/gfx/geometry/mojo/geometry_struct_traits.h"
 #include "ui/latency/latency_info.h"
@@ skipping 32 matching lines @@
   static Element& GetValue(Iterator& iterator) { return *iterator; }
 
   static size_t GetSize(const ui::LatencyInfo::LatencyMap& input) {
     return input.size();
   }
 };
 
 template <>
 struct StructTraits<ui::mojom::LatencyComponentDataView,
                     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);
   static base::TimeTicks first_event_time(
       const ui::LatencyInfo::LatencyComponent& component);
   static base::TimeTicks last_event_time(
       const ui::LatencyInfo::LatencyComponent& component);
   static bool Read(ui::mojom::LatencyComponentDataView data,
                    ui::LatencyInfo::LatencyComponent* out);
@@ skipping 37 matching lines @@
   static ui::mojom::SourceEventType source_event_type(
       const ui::LatencyInfo& info);
   static base::TimeDelta expected_queueing_time_on_dispatch(
       const ui::LatencyInfo& info);
   static bool Read(ui::mojom::LatencyInfoDataView data, ui::LatencyInfo* out);
 };
 
 }  // namespace mojo
 
 #endif  // UI_LATENCY_MOJO_LATENCY_INFO_STRUCT_TRAITS_H_