Summary:
Several reasons:
* We are fulfilling a promise that RCTScheduler is just a very thin interop proxy between C++ and Objective-C;
* We have to pass all parameters down to Scheduler anyway, so instead of creating all of them separately and then passing one-by-one, we consolidate them into Context created where we have all those values.
In the future, we probably will move it to some dedicated place.
Reviewed By: mdvacca
Differential Revision: D9884892
fbshipit-source-id: f1d5744e4044bc4bdfe53ec9a97ee61dcf0c60c2