Test that CanvasAgent.requestNode can properly resolve the owner canvas node.


== Running test suite: Canvas.requestNode
-- Running test case: Canvas.requestNode.validCanvasId
PASS: Canvas "CSS canvas “css”" has node with valid id.
PASS: Canvas "CSS canvas “css”" has node with type "CANVAS".
PASS: Canvas "Canvas 1" has node with valid id.
PASS: Canvas "Canvas 1" has node with type "CANVAS".
PASS: Canvas "Canvas 2" has node with valid id.
PASS: Canvas "Canvas 2" has node with type "CANVAS".

-- Running test case: Canvas.requestNode.invalidCanvasId
PASS: Should produce an error.
Error: Missing canvas for given canvasId