Make ShadowRoot.cloneNode() throw NotSupportedError, instead of DataCloneError.

See the spec change: https://github.com/w3c/webcomponents/issues/393

I think the previous behavior should be considered as a bug of the spec.
It would be okay to change the behavior since the compatibility risk is very low.

BUG=531990

Review URL: https://codereview.chromium.org/1831753002

Cr-Commit-Position: refs/heads/master@{#383240}
4 files changed