Summary:
We use projectRoots to limit crawling of jest-haste-map in large codebases. Since this implies multiple projects roots, it makes it very hard (or impossible) to reliably cache dependency resolutions.
If we can replace this with a single project root and a set of watch roots, we can have relative path resolutions for all dependencies which van be cached.
Reviewed By: rafeca
Differential Revision: D8450498
fbshipit-source-id: 830c21e847c3236e42d5414a8587508cb73864bd
c5ce762697