Update Surface ID Terminology

cc/ipc/surface_id_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_ID_STRUCT_TRAITS_H_
 #define CC_IPC_SURFACE_ID_STRUCT_TRAITS_H_
 
 #include "cc/surfaces/surface_id.h"
 
 namespace mojo {
 
 // This template is fully specialized as cc::mojom::SurfaceId and
 // as cc::mojom::blink::SurfaceId, in generated .mojom.h and .mojom-blink.h
 // respectively.
 template <typename T>
 struct StructTraits<T, cc::SurfaceId> {
-  static uint32_t id_namespace(const cc::SurfaceId& id) {
-    return id.id_namespace();
-  }
+  static uint32_t client_id(const cc::SurfaceId& id) { return id.client_id(); }
 
   static uint32_t local_id(const cc::SurfaceId& id) { return id.local_id(); }
 
   static uint64_t nonce(const cc::SurfaceId& id) { return id.nonce(); }
 
   static bool Read(typename T::DataView data, cc::SurfaceId* out) {
-    *out = cc::SurfaceId(data.id_namespace(), data.local_id(), data.nonce());
+    *out = cc::SurfaceId(data.client_id(), data.local_id(), data.nonce());
     return true;
   }
 };
 
 }  // namespace mojo
 
 #endif  // CC_IPC_SURFACE_ID_STRUCT_TRAITS_H_