Calculate all the transitive deps before rendering any fixtures.
Calculate all the transitive deps before rendering any fixtures.

Summary:
This avoids having to recalculate deps for every fixture -- useful
when using this as a load balancer.  It also simplifies the code a
bit, maybe, by keeping all the deps-handling in one function.

Test Plan:
tools/benchmark_ka_component.js ~/khan/webapp/javascript/*-package/*.fixture.*

Ran to completion and had lines like:
   javascript/translations-dashboard-package/dash-treeview.jsx: 9647

Reviewers: jlfwong

Reviewed By: jlfwong

Subscribers: john, emily

Differential Revision: https://phabricator.khanacademy.org/D24687

Khan/react-render-server,Khan/react-render-server,Khan/react-render-server