fixup! fixup! fixup! fixup! fixup! update flow

Author: raphamorim

packages/react-reconciler/src/ReactFiberReconciler.js

@@ -49,7 +49,7 @@ type OpaqueRoot = FiberRoot;
 
 export type HostConfig<T, P, I, TI, HI, PI, C, CC, CX, PL> = {
   getRootHostContext(rootContainerInstance: C): CX,
-  getChildHostContext(parentHostContext: any, type: T, instance: any): CX,
+  getChildHostContext(parentHostContext: CX, type: T, instance: ?C): CX,
   getPublicInstance(instance: I | TI): PI,
 
   createInstance(