custom-elements: Element created by createElementNS(ns, qname, options) with...

custom-elements: Element created by createElementNS(ns, qname, options) with valid custom element name and undefined options should be upgraded immediately

createElementNS(XHTML_NS, 'my-element', undefined) was not being
upgraded immediatedly, though both createElementNS(XHTML_NS,
'my-element') and createElementNS(XHTML_NS, 'my-element', {}) were.

Bug: 841725
Change-Id: Iccc4f0e98b1de65288381dd9ac106e71bfc5d0c8
Reviewed-on: https://chromium-review.googlesource.com/1096812Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566374}

third_party/WebKit/LayoutTests/external/wpt/custom-elements/Document-createElementNS.html

@@ -31,6 +31,14 @@ test(() => {
   assert_false((new Document()).createElementNS(xhtmlNS, 'x-foo', {}) instanceof HTMLUnknownElement);
 }, 'autonomous: document.createElementNS should not create HTMLUnknownElement for a valid custom element name');
 
+test(() => {
+  class MyElement3 extends HTMLElement {};
+  customElements.define('my-autonomous3', MyElement3);
+
+  const instance = document.createElementNS('http://www.w3.org/1999/xhtml', 'my-autonomous3', undefined);
+  assert_true(instance instanceof MyElement3);
+}, 'autonomous: document.createElementNS with undefined options value should be upgraded.');
+
 test(() => {
   class MyBuiltinElement extends HTMLElement {};
 

third_party/blink/renderer/core/dom/document.cc

@@ -1046,6 +1046,9 @@ Element* Document::createElementNS(const AtomicString& namespace_uri,
                                    const AtomicString& qualified_name,
                                    const StringOrDictionary& string_or_options,
                                    ExceptionState& exception_state) {
+  if (string_or_options.IsNull())
+    return createElementNS(namespace_uri, qualified_name, exception_state);
+
   // 1. Validate and extract
   QualifiedName q_name(
       CreateQualifiedName(namespace_uri, qualified_name, exception_state));