Ensuring we continue to use strike tags for legacy strikethrough execCommands, not s tags. See https://bugs.webkit.org/show_bug.cgi?id=53475

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".


PASS Strikethrough of "Don't change expected results for me!" yields "<strike>Don't change expected results for me!</strike>"
PASS successfullyParsed is true

TEST COMPLETE

