Tests that console.assert() will dump a message and stack trace with source URLs and line numbers.

console-assert.js:16 Assertion failed: 1
b @ console-assert.js:16
a @ console-assert.js:22
setTimeout
(anonymous) @ console-assert.js:39
console-assert.js:17 Assertion failed: a b
b @ console-assert.js:17
a @ console-assert.js:22
setTimeout
(anonymous) @ console-assert.js:39