FrameSinkIds use to WindowIds in window server, Process ID/Route ID in renderer

services/ui/ws/server_window_surface.cc

 // Copyright 2015 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.
 
 #include "services/ui/ws/server_window_surface.h"
 
 #include "base/callback.h"
 #include "base/message_loop/message_loop.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/quads/shared_quad_state.h"
 #include "cc/quads/surface_draw_quad.h"
 #include "services/ui/surfaces/display_compositor.h"
 #include "services/ui/ws/server_window.h"
 #include "services/ui/ws/server_window_delegate.h"
 #include "services/ui/ws/server_window_surface_manager.h"
 
 namespace ui {
 namespace ws {
 
 ServerWindowSurface::ServerWindowSurface(
     ServerWindowSurfaceManager* manager,
+    const cc::FrameSinkId& frame_sink_id,
     mojo::InterfaceRequest<Surface> request,
     mojom::SurfaceClientPtr client)
-    : frame_sink_id_(manager->window()
-                         ->delegate()
-                         ->GetDisplayCompositor()
-                         ->GenerateNextClientId(),
-                     0),
+    : frame_sink_id_(frame_sink_id),
       manager_(manager),
       surface_id_allocator_(frame_sink_id_),
       surface_factory_(frame_sink_id_, manager_->GetSurfaceManager(), this),
       client_(std::move(client)),
       binding_(this, std::move(request)) {
   cc::SurfaceManager* surface_manager = manager_->GetSurfaceManager();
   surface_manager->RegisterFrameSinkId(frame_sink_id_);
   surface_manager->RegisterSurfaceFactoryClient(frame_sink_id_, this);
 }
 
@@ skipping 54 matching lines @@
   client_->ReturnResources(mojo::Array<cc::ReturnedResource>::From(resources));
 }
 
 void ServerWindowSurface::SetBeginFrameSource(
     cc::BeginFrameSource* begin_frame_source) {
   // TODO(tansell): Implement this.
 }
 
 }  // namespace ws
 }  // namespace ui