google/traceur-compiler — pull request #955 by rwaldron (2014-04-11 20:16:16+00:00)
Title: Update Object.assign signature. Fixes gh-954

Updates Object.assign to accept an arbitrary number of source objects whose own, enumerable property names and corresponding values are copied to the target. (Per April 9 TC39 consensus)

I've previously signed the CLA

Signed-off-by: Rick Waldron