ES6 spec for DataView is not fully finished, but Blink, WebKit and
Firefox agree in that for DataView use of getters/setters with no
arguments should result in exceptions, while undefined offset argument
is the same as zero.

R=bmeurer@chromium.org, rossberg@chromium.org

Review URL: https://codereview.chromium.org/18313007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15607 ce2b1a6d-e550-0410-aec6-3dcde31c8c00