Fix stupid mistakes in metagrammar-test.js
Fix stupid mistakes in metagrammar-test.js

The mistakes weren't caught because the first one introduces a syntax
error, causing the whole test suite not to load. Unfortunately, QUnit
didn't complain so I missed this.

The real commit these changes belong to is
33a1a7c1e996dcf0d1c423b6db9740ff1ecea746.

Mingun/pegjs,GerHobbelt/pegjs,pegjs/pegjs,jlturner/pegjs,jlturner/pegjs,Sciumo/pegjs,mcanthony/pegjs,pegjs/pegjs,wwall/pegjs-fn,crguezl/pegjs,Mingun/pegjs,wwall/pegjs-fn,mcanthony/pegjs,luisvt/pegjs,crguezl/pegjs,Sciumo/pegjs,luisvt/pegjs,GerHobbelt/pegjs