WIP: Propagate SurfaceID up window tree hierarchy

cc/ipc/surface_sequence_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_SURFACE_SEQUENCE_STRUCT_TRAITS_H_
 #define CC_IPC_SURFACE_SEQUENCE_STRUCT_TRAITS_H_
 
 #include "cc/ipc/surface_sequence.mojom-shared.h"
 #include "cc/surfaces/surface_sequence.h"
 
 namespace mojo {
 
 template <>
 struct StructTraits<cc::mojom::SurfaceSequenceDataView, cc::SurfaceSequence> {
-  static uint32_t client_id(const cc::SurfaceSequence& id) {
-    return id.client_id;
+  static const cc::FrameSinkId& frame_sink_id(const cc::SurfaceSequence& id) {
+    return id.frame_sink_id;
   }
 
   static uint32_t sequence(const cc::SurfaceSequence& id) {
     return id.sequence;
   }
 
   static bool Read(cc::mojom::SurfaceSequenceDataView data,
                    cc::SurfaceSequence* out) {
-    *out = cc::SurfaceSequence(data.client_id(), data.sequence());
+    cc::FrameSinkId frame_sink_id;
+    if (!data.ReadFrameSinkId(&frame_sink_id))
+      return false;
+    *out = cc::SurfaceSequence(frame_sink_id, data.sequence());
     return true;
   }
 };
 
 }  // namespace mojo
 
 #endif  // CC_IPC_SURFACE_SEQUENCE_STRUCT_TRAITS_H_