Fix collected properties in window-property-collector.js

This change made bug 347020 obvious in the sense that without CL 208333018,
LayoutTests would crash.

A side effect of this change is that mac-specific results can be removed.

BUG=347020

Review URL: https://codereview.chromium.org/208243016

git-svn-id: svn://svn.chromium.org/blink/trunk@170171 bbb929c8-8fbe-4397-9dbb-9b2b20218538