fixup! Add a force_timeout function to tests.
fixup! Add a force_timeout function to tests.

hallvors/testharness.js,zqzhang/testharness.js,bboyle/testharness.js,ayg/testharness.js,RatneshThakur/testharness.js,jyasskin/testharness.js,hallvors/testharness.js,jyasskin/testharness.js