Tests if repeated loading of non-existent img.src resources doesn't deliver onload.

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

PASS Received onerror for non-existent img.src
PASS Received onerror for non-existent img.src
PASS Received error event repeatedly.
PASS Received onload for broken img.src
PASS successfullyParsed is true

TEST COMPLETE