Port r20817 (e7a84c1)

Original commit message:
Just wanted to add two constructors to a datatype, how ugly can it get?

BUG=
R=plind44@gmail.com

Review URL: https://codereview.chromium.org/240463004

Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20822 ce2b1a6d-e550-0410-aec6-3dcde31c8c00