Summary:
While converting Bloks-Script plugin, Timur found a bug where the message queue wasn't processed.
Although queue processing was unit tested, the integration into the rendering lifecycle wasn't explicitly tested and missed a TODO that already signalled this should have been implemented.
Added a unit test to verify the bug and fix. Also tested in a running Flipper instance with the converted plugin (next diff)
Reviewed By: jknoxville
Differential Revision: D23263909
fbshipit-source-id: 63783c980247bdf6c93d00a46881d7d0eb291d09
76b72f3d77