Temporarily mark reserved-words-as-property as possibly failing.

V8 is changing an error message and Blink will disable this test temporarily,
too. This CL will keep the tree green until Blink is rolled into V8.

BUG=3126
LOG=N
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/152863004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19071 ce2b1a6d-e550-0410-aec6-3dcde31c8c00