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

V8 is changing an error message, so this will start failing when V8 rolls. (See
bug.)

R=jochen@chromium.org
BUG=

Review URL: https://codereview.chromium.org/135533008

git-svn-id: svn://svn.chromium.org/blink/trunk@166395 bbb929c8-8fbe-4397-9dbb-9b2b20218538