Revert "move RoutingContext tests to their own file"

didn't look closely enough, turns out these are RoutingContext tests!

This reverts commit 824c816.

Author: ryanflorence

modules/__tests__/Router-test.js

@@ -277,6 +277,105 @@ describe('Router', function () {
 
   })
 
+  describe('RoutingContext', function () {
+    it('applies custom RoutingContext', function (done) {
+      const Parent = ({ children }) => <span>parent:{children}</span>
+      const Child = () => <span>child</span>
+
+      class LabelWrapper extends Component {
+        constructor(props, context) {
+          super(props, context)
+          this.createElement = this.createElement.bind(this)
+        }
+
+        createElement(component, props) {
+          const { label, createElement } = this.props
+
+          return (
+            <span>
+              {label}-inner:{createElement(component, props)}
+            </span>
+          )
+        }
+
+        render() {
+          const { label, children } = this.props
+          const child = React.cloneElement(children, {
+            createElement: this.createElement
+          })
+
+          return (
+            <span>
+              {label}-outer:{child}
+            </span>
+          )
+        }
+      }
+
+      LabelWrapper.defaultProps = {
+        createElement: React.createElement
+      }
+
+      const CustomRoutingContext = props => (
+        <LabelWrapper label="m1">
+          <LabelWrapper label="m2">
+            <RoutingContext {...props} />
+          </LabelWrapper>
+        </LabelWrapper>
+      )
+
+      render((
+        <Router
+          history={createHistory('/child')}
+          RoutingContext={CustomRoutingContext}
+        >
+          <Route path="/" component={Parent}>
+            <Route path="child" component={Child} />
+          </Route>
+        </Router>
+      ), node, function () {
+        // Note that the nesting order is inverted for `createElement`, because
+        // the order of function application is outermost-first.
+        expect(node.textContent).toBe(
+          'm1-outer:m2-outer:m2-inner:m1-inner:parent:m2-inner:m1-inner:child'
+        )
+        done()
+      })
+    })
+
+    it('passes router props to custom RoutingContext', function (done) {
+      const MyComponent = () => <div />
+      const route = { path: '/', component: MyComponent }
+
+      const Wrapper = (
+        { routes, components, foo, RoutingContext, children }
+      ) => {
+        expect(routes).toEqual([ route ])
+        expect(components).toEqual([ MyComponent ])
+        expect(foo).toBe('bar')
+        expect(RoutingContext).toNotExist()
+        done()
+
+        return children
+      }
+      const CustomRoutingContext = props => (
+        <Wrapper {...props}>
+          <RoutingContext {...props} />
+        </Wrapper>
+      )
+
+      render((
+        <Router
+          history={createHistory('/')}
+          routes={route}
+          RoutingContext={CustomRoutingContext}
+          foo="bar"
+        />
+      ), node)
+    })
+
+  })
+
   describe('async components', function () {
     let componentSpy, RoutingSpy