Check if input.value="" clears an input with partially-specified value.

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

Empty text: --------- ----
PASS eventSender.keyDown("ArrowUp"); getUserAgentShadowTextContent(input) is not emptyText
PASS input.value = ""; getUserAgentShadowTextContent(input) is emptyText
PASS successfullyParsed is true

TEST COMPLETE