HTMLCanvasElement.toDataURL should use IDL 'any' to avoid using custom binding.

Source/core/html/HTMLCanvasElement.idl

 /*
  * Copyright (C) 2006, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 13 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 typedef (CanvasRenderingContext2D or WebGLRenderingContext) RenderingContext;
 
 interface HTMLCanvasElement : HTMLElement {
 
     attribute long width;
     attribute long height;
 
-    [Custom, RaisesException] DOMString toDataURL([TreatUndefinedAs=NullString, Default=Undefined] optional DOMString? type);
+    [RaisesException] DOMString toDataURL([TreatUndefinedAs=NullString, Default=Undefined] optional DOMString? type, optional any arguments);

[Jens Widell, 2015/02/11 20:18:55]

BTW, the first argument could equivalently be declared as "optional DOMString?
type = null" (without any extended attributes.)

 
     // Note: this differs deliberately from the specified Web IDL for this function:
     //     RenderingContext? getContext(DOMString contextId, any... arguments);
     // in order to eliminate the custom binding. It is functionally equivalent.
     //
     // The PermissiveDictionaryConversion extended attribute is needed to allow the
     // autogenerated code to match the behavior of the custom binding. Web IDL
     // requires throwing TypeError if the incoming argument is not an object type
     // (and is not undefined or null). The binding must ignore this.
     //
     // Also note: the only reason this must return type "any" is to allow the
     // InspectorInstrumentation wrappers to be called for canvases. If that could be
     // handled differently the return type could be changed to "RenderingContext?"
     // and the [CallWith=ScriptState] extended attribute removed.
     [CallWith=ScriptState] any getContext([Default=Undefined] optional DOMString contextId, [PermissiveDictionaryConversion] optional CanvasContextCreationAttributes attributes);
 };