Add OffscreenCanvas to ImageBitmapSource union typedef

third_party/WebKit/Source/core/imagebitmap/ImageBitmapFactories.idl

 /*
  * Copyright (c) 2013, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 17 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 // https://html.spec.whatwg.org/#imagebitmapfactories
 
 typedef (HTMLImageElement or
          HTMLVideoElement or
          HTMLCanvasElement or
          Blob or
          ImageData or
-         ImageBitmap) ImageBitmapSource;
+         ImageBitmap or
+         OffscreenCanvas) ImageBitmapSource;
 
 [
     LegacyTreatAsPartialInterface,
     NoInterfaceObject, // Always used on target of 'implements'
     Exposed=(Window,Worker),
 ] interface ImageBitmapFactories {
     [CallWith=ScriptState, RaisesException] Promise createImageBitmap(
         ImageBitmapSource imageBitmap, optional ImageBitmapOptions options);
     [CallWith=ScriptState, RaisesException] Promise createImageBitmap(
         ImageBitmapSource imageBitmap, long sx, long sy, long sw, long sh, optional ImageBitmapOptions options);
 };
 
 Window implements ImageBitmapFactories;
 WorkerGlobalScope implements ImageBitmapFactories;