Summary: Depending on the timing of the method call from JS to a CxxModule, we may be accessing memory that has been deallocated, causing exception to RN runtime. This fixes it.
Reviewed By: JoshuaGross, mdvacca
Differential Revision: D14033831
fbshipit-source-id: 5a77aa41223b1fc3146dcf78b7f8e93375605d6d