Tests various use cases when cloning MessagePorts.

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

PASS channel.port1.postMessage('msg', [channel.port1]) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': Port at index 0 contains the source port..
Posting port to entangled pair neuters the port and does nothing else:
PASS channel2.port1.postMessage('msg', [channel.port2]) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': Port at index 0 is already neutered..
Posting a detached ArrayBuffer should throw.
PASS channel.port1.postMessage(arrayBuffer, []) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': An ArrayBuffer is detached and could not be cloned..
Posting a detached ArrayBufferView should throw.
PASS channel.port1.postMessage('msg', [uint16Array]) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': Value at index 0 does not have a transferable type..
PASS channel.port1.postMessage(uint16Array, []) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': An ArrayBuffer is detached and could not be cloned..
PASS channel.port1.postMessage('msg', [channel2.port1]) threw exception DataCloneError: Failed to execute 'postMessage' on 'MessagePort': Port at index 0 is already neutered..
PASS testEvent.ports.length is 1
PASS parseInt(testEvent.data) is 1
PASS parseInt(testEvent.data) is 2
PASS parseInt(testEvent.data) is 3
PASS Posted messages to cloned port.
PASS testEvent.data is 'testme'
PASS testEvent.ports is not null
PASS testEvent.ports.length is 1
PASS testEvent.data is 'closed'
PASS successfullyParsed is true

TEST COMPLETE