2nd arg of document.createElement should be an object

third_party/WebKit/Source/core/frame/Deprecation.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 "core/frame/Deprecation.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/FrameConsole.h"
 #include "core/frame/FrameHost.h"
@@ skipping 358 matching lines @@
 
     case UseCounter::V8SVGSVGElement_Viewport_AttributeGetter:
         return willBeRemoved("SVGSVGElement.viewport", 55, "5686865248124928");
 
     case UseCounter::V8SVGViewElement_ViewTarget_AttributeGetter:
         return willBeRemoved("SVGViewElement.viewTarget", 56, "5665473114931200");
 
     case UseCounter::NavigatorPointerEnabled:
         return "Navigator.pointerEnabled is a non-standard API added for experiments only. It will be removed in near future.";
 
+    case UseCounter::DocumentCreateElement2ndArg:

[dominicc (has gone to gerrit), 2016/09/15 01:19:24]

Maybe give this a more descriptive name, because createElement having a second
argument isn't deprecated; it's the future! Maybe mention ...StringHandling or
something in the name.

+        return "Document.createElement second argument string will be replaced in near future with the dictionary. See https://dom.spec.whatwg.org/#dom-document-createelement.";

[dominicc (has gone to gerrit), 2016/09/15 01:19:24]

Maybe make this more explicit: Change to passing a dictionary with 'is' *now*,
because that will work, and passing a string will stop being supported soon.

+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();
     }
 }
 
 } // namespace blink