Sync DOMImplementation.createDocument() IDL with spec

Sync DOMImplementation.createDocument() IDL with spec

https://dom.spec.whatwg.org/#interface-domimplementation

Because DOMImplementation::createDocument calls qualifiedName.isEmpty()
there is no observable difference when qualifiedName is null.

The added [TypeChecking=Interface] only affects the generated code for
the doctype argument, where passing a non-null, non-DocType object will
now throw an exception.

Firefox Nightly and IE11 pass all of the new tests, with the exception
of IE11 throwing an exception when the doctype argument is undefined. In
other words, the cases where we now throw exceptions already throw
exceptions in Firefox and IE, making it likely Web compatible.

TEST=LayoutTests/fast/dom/DOMImplementation/createDocument-doctype-err.html

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=186779

[philipj_slow, 2014-12-08 11:34:17]

philipj@opera.com changed reviewers:
+ mkwst@chromium.org

[philipj_slow, 2014-12-08 11:34:17]

PTAL

[Mike West, 2014-12-09 14:09:24]

LGTM.

[philipj_slow, 2014-12-09 14:25:50]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2014-12-09 14:26:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/762383004/1

[commit-bot: I haz the power, 2014-12-09 14:28:41]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=186779