Transfer components of SurfaceId in OffscreenCanvas

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 19 matching lines @@
 }
 
 OffscreenCanvas* HTMLCanvasElementModule::transferControlToOffscreenInternal(HTMLCanvasElement& canvas, ExceptionState& exceptionState)
 {
     if (canvas.renderingContext()) {
         exceptionState.throwDOMException(InvalidStateError, "Cannot transfer control from a canvas that has a rendering context.");
         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.
+        offscreenCanvas->setSurfaceId(bridge->getSurfaceId().client_id(), bridge->getSurfaceId().local_id(), bridge->getSurfaceId().nonce());
+    }
     return offscreenCanvas;
 }
 
 }