jstests/sharding/mrShardedOutput.js passes a function and a timeout to assert.soon on lines 111 to 114.

    assert.soon(function(){
        return hasChunkOnShard("test.foo", shards[0]._id) && 
               hasChunkOnShard("test.foo", shards[1]._id);
    }, 2 * 60 * 1000);

This does not match the function signature for assert.soon:

assert.soon = function(f, msg, timeout /*ms*/, interval) {

The timeout will not be used, but will be displayed as the error message if the default 30 second timeout occurs.