Add support for skipping using a worker in certain cases (createGraphics)

Summary:
createGraphics currently creates a whole new Processing environment and fails within a worker.
This problem may be able to be fixed while still using the worker, but I don't think the time investment is worth it currently.

Test Plan: - Run the code from this program: https://www.khanacademy.org/cs/creategraphics-problem/5830471485489152

Reviewers: pamela, john

Subscribers: #cs

Maniphest Tasks: T3285

Differential Revision: http://phabricator.khanacademy.org/D14399