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

third_party/WebKit/Source/modules/canvas/HTMLCanvasElementModule.cpp

 // 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.
 
 #include "modules/canvas/HTMLCanvasElementModule.h"
 
 #include "core/dom/DOMNodeIds.h"
 #include "core/html/canvas/CanvasContextCreationAttributes.h"
 #include "core/html/canvas/CanvasRenderingContext.h"
 #include "core/offscreencanvas/OffscreenCanvas.h"
@@ skipping 46 matching lines @@
     return nullptr;
   }
   OffscreenCanvas* offscreenCanvas =
       OffscreenCanvas::create(canvas.width(), canvas.height());
   offscreenCanvas->setAssociatedCanvasId(DOMNodeIds::idForNode(&canvas));
 
   CanvasSurfaceLayerBridge* bridge = canvas.surfaceLayerBridge();
   if (bridge) {
     // If a bridge exists, it means canvas.createSurfaceLayer() has been called
     // and its SurfaceId has been populated as well.
-    // TODO(fsamuel): Plumb FrameSinkId into blink.
     offscreenCanvas->setSurfaceId(
         bridge->getSurfaceId().frame_sink_id().client_id(),
+        bridge->getSurfaceId().frame_sink_id().sink_id(),
         bridge->getSurfaceId().local_id(), bridge->getSurfaceId().nonce());
   }
   return offscreenCanvas;
 }
 }