rebaseline the old tests that have languished in http://src.chromium.org/viewvc/chrome/trunk/src/webkit/tools/layout_tests/test_expectations.txt?view=markup
never mind... I ran the steps in https://goto.google.com/HowToRebaselineWebkitTests and found that these tests must have already been rebaselined. Going ahead and removing the old tests from chrome test_expectations in https://chromiumcodereview.appspot.com/9178037/ ('Remove long-ago rebaselined tests from chrome test_expectations')