[cc] Adds source_id and sequence_number to BeginFrameArgs.

cc/ipc/begin_frame_args_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 CC_IPC_BEGIN_FRAME_ARGS_STRUCT_TRAITS_H_
 #define CC_IPC_BEGIN_FRAME_ARGS_STRUCT_TRAITS_H_
 
 #include "cc/ipc/begin_frame_args.mojom-shared.h"
 #include "cc/output/begin_frame_args.h"
 
 namespace mojo {
 
 template <>
 struct StructTraits<cc::mojom::BeginFrameArgsDataView, cc::BeginFrameArgs> {
   static base::TimeTicks frame_time(const cc::BeginFrameArgs& args) {
     return args.frame_time;
   }
 
   static base::TimeTicks deadline(const cc::BeginFrameArgs& args) {
     return args.deadline;
   }
 
   static base::TimeDelta interval(const cc::BeginFrameArgs& args) {
     return args.interval;
   }
 
+  static uint64_t sequence_number(const cc::BeginFrameArgs& args) {
+    return args.sequence_number;
+  }
+
+  static uint32_t source_id(const cc::BeginFrameArgs& args) {
+    return args.source_id;
+  }
+
   static cc::mojom::BeginFrameArgsType type(const cc::BeginFrameArgs& args) {
     return static_cast<cc::mojom::BeginFrameArgsType>(args.type);
   }
 
   static bool on_critical_path(const cc::BeginFrameArgs& args) {
     return args.on_critical_path;
   }
 
   static bool Read(cc::mojom::BeginFrameArgsDataView data,
                    cc::BeginFrameArgs* out) {
     if (!data.ReadFrameTime(&out->frame_time) ||
         !data.ReadDeadline(&out->deadline) ||
         !data.ReadInterval(&out->interval)) {
       return false;
     }
+    out->source_id = data.source_id();
+    out->sequence_number = data.sequence_number();
     out->type =
         static_cast<cc::BeginFrameArgs::BeginFrameArgsType>(data.type());
     out->on_critical_path = data.on_critical_path();
     return true;
   }
 };
 
 }  // namespace mojo
 
 #endif  // CC_IPC_BEGIN_FRAME_ARGS_STRUCT_TRAITS_H_