Add additional babel transform
Summary: Add another optional runtime flag to HHVM called -Eval.AdditionalBabelTransforms=<path-to-extra-transforms> which, if present, hackc will invoke before calling into the HHJS babel transform. We do this because we want to keep HHJS code as WWW agnostic as possible. Using this new flag, we will introduce another babel transform pipeline that lives in WWW that will lower WWW-specific code into a form consumable by HHJS.
Reviewed By: alexmckenley
Differential Revision:
D14626984
fbshipit-source-id:
168342435231e4fa36e093ecd4b7b2cf1fd85339