Summary:
While debugging internally, we have found that modules are almost always registered
with their "RK" or "RCT" prefixes dropped.
However, if a view is named `RCTFooView` and needs `RCTFooViewManager` to render natively, it will almost never find it because `RCT` was dropped from the key to the ViewManager instance.
In the event you look for a `ViewManager` and don't find it, this strips any "React" prefixes from your key and tries ones more time.
Reviewed By: spredolac
Differential Revision: D10734005
fbshipit-source-id: 2bfa6f19830f14f09af2fe7dc7e44b7e26e0ac3f
6534718a18