fix: fix more flow issues

Author: jedwards1211

src/defaults.js

@@ -24,7 +24,7 @@ export function defaultComposeReducers<S, A>(...reducers: Array<Reducer<S, A>>):
   }
 }
 
-export function defaultCreateMiddleware<S, A: {type: $Subtype<string>}>(middlewares: {[actionType: string]: Middleware<S, A>}): Middleware<S, A> {
+export function defaultCreateMiddleware<S, A: {type: $Subtype<String>}, D>(middlewares: {[actionType: string]: Middleware<S, A>}): Middleware<S, A> {
   return (store: MiddlewareAPI<S, A>) => (next: Dispatch<A>) => (action: A) => {
     const middleware = middlewares[action.type]
     if (!middleware) return next(action)

src/featureReducersReducer.js

@@ -6,7 +6,7 @@ import {createSelector} from 'reselect'
 
 import {defaultComposeReducers} from './defaults'
 
-export default function featureReducersReducer<S, A>(
+export default function featureReducersReducer<S, A: {type: $Subtype<string>}>(
   config?: {
     getFeatures?: (state: S) => ?Features<S, A>,
     composeReducers?: ComposeReducers<S, A>,

src/featuresReducer.js

@@ -6,7 +6,7 @@ import {ADD_FEATURE, INSTALL_FEATURE, REPLACE_FEATURE} from './actions'
 
 import {defaultCreateReducer} from './defaults'
 
-export default function featuresReducer<S, A>(
+export default function featuresReducer<S, A: {type: $Subtype<string>}>(
   config?: {
     createReducer?: CreateReducer<Features<S, A>, FeatureAction>,
   } = {}

src/loadFeatureMiddleware.js

@@ -11,8 +11,7 @@ export default function loadFeatureMiddleware<S, A: {type: $Subtype<string>}>(
     getFeatureStates?: (state: S) => ?FeatureStates,
     createMiddleware?: (middlewares: {[actionType: string]: Middleware<S, A>}) => Middleware<S, A>,
   } = {}
-  // $FlowFixMe
-): Middleware<S, A | FeatureAction> {
+): Middleware<S, A> {
   const getFeatures = config.getFeatures || ((state: any) => state && state.features)
   const getFeatureStates = config.getFeatureStates || ((state: any) => state && state.featureStates)
   const createMiddleware = config.createMiddleware || defaultCreateMiddleware