Change children prop from react-router to only be a Element type

Judging by
https://github.com/rackt/react-router/blob/master/docs/API.md#children-1
and a few inspections in the code, as well as tests, the `children`
prop injected into routes can only ever be a single React Element
object.

This allows us to easily get the active route of a child (if there is
an active route) by querying the `children`’s route prop.

js/components/app_base.js

@@ -15,14 +15,10 @@ export default function AppBase(App) {
         displayName: 'AppBase',
 
         propTypes: {
+            children: React.PropTypes.element.isRequired,
             history: React.PropTypes.object.isRequired,
             location: React.PropTypes.object.isRequired,
-            routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired,
-
-            children: React.PropTypes.oneOfType([
-                React.PropTypes.arrayOf(React.PropTypes.element),
-                React.PropTypes.element
-            ])
+            routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired
         },
 
         mixins: [History],
@@ -42,10 +38,20 @@ export default function AppBase(App) {
         },
 
         render() {
+            const { children } = this.props;
+
+            // Get the currently active route of the app by using the injected route parameter
+            // on the currently active child route.
+            // Note that despite its name, this.props.children can only ever be a single
+            // React.PropTypes.element.
+            const activeRoute = children.props.route;
+
             return (
                 <div>
-                    <App {...this.props} />
                     <Footer />
+                    <App
+                        {...this.props}
+                        activeRoute={activeRoute} />
                     <GlobalNotification />
                     <div id="modal" className="container" />
                 </div>

js/components/ascribe_app.js

@@ -8,16 +8,13 @@ import Header from './header';
 
 let AscribeApp = React.createClass({
     propTypes: {
-        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired,
-
-        children: React.PropTypes.oneOfType([
-            React.PropTypes.arrayOf(React.PropTypes.element),
-            React.PropTypes.element
-        ])
+        activeRoute: React.PropTypes.object.isRequired,
+        children: React.PropTypes.element.isRequired,
+        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired
     },
 
     render() {
-        const { children, routes } = this.props;
+        const { activeRoute, children, routes } = this.props;
 
         return (
             <div className="ascribe-default-app">

js/components/whitelabel/prize/portfolioreview/pr_app.js

@@ -19,13 +19,10 @@ import { getCookie } from '../../../../utils/fetch_api_utils';
 
 let PRApp = React.createClass({
     propTypes: {
+        activeRoute: React.PropTypes.object.isRequired,
+        children: React.PropTypes.element.isRequired,
         history: React.PropTypes.object.isRequired,
-        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired,
-
-        children: React.PropTypes.oneOfType([
-            React.PropTypes.arrayOf(React.PropTypes.element),
-            React.PropTypes.element
-        ])
+        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired
     },
 
     getInitialState() {
@@ -60,7 +57,7 @@ let PRApp = React.createClass({
 
 
     render() {
-        const { children, history, routes } = this.props;
+        const { activeRoute, children, history, routes } = this.props;
         const { currentUser } = this.state;
         const subdomain = getSubdomain();
 

js/components/whitelabel/prize/simple_prize/prize_app.js

@@ -13,17 +13,14 @@ import { getSubdomain } from '../../../../utils/general_utils';
 
 let PrizeApp = React.createClass({
     propTypes: {
+        activeRoute: React.PropTypes.object.isRequired,
+        children: React.PropTypes.element.isRequired,
         history: React.PropTypes.object.isRequired,
-        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired,
-
-        children: React.PropTypes.oneOfType([
-            React.PropTypes.arrayOf(React.PropTypes.element),
-            React.PropTypes.element
-        ])
+        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired
     },
 
     render() {
-        const { children, history, routes } = this.props;
+        const { activeRoute, children, history, routes } = this.props;
         const subdomain = getSubdomain();
 
         // The second element of routes is always the active component object, where we can

js/components/whitelabel/wallet/wallet_app.js

@@ -11,17 +11,14 @@ import { getSubdomain } from '../../../utils/general_utils';
 
 let WalletApp = React.createClass({
     propTypes: {
+        activeRoute: React.PropTypes.object.isRequired,
+        children: React.PropTypes.element.isRequired,
         history: React.PropTypes.object.isRequired,
-        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired,
-
-        children: React.PropTypes.oneOfType([
-            React.PropTypes.arrayOf(React.PropTypes.element),
-            React.PropTypes.element
-        ])
+        routes: React.PropTypes.arrayOf(React.PropTypes.object).isRequired
     },
 
     render() {
-        const { children, history, routes } = this.props;
+        const { activeRoute, children, history, routes } = this.props;
         const subdomain = getSubdomain();
 
         // The second element of routes is always the active component object, where we can

js/routes.js

@@ -6,7 +6,7 @@ import { Route } from 'react-router';
 import getPrizeRoutes from './components/whitelabel/prize/prize_routes';
 import getWalletRoutes from './components/whitelabel/wallet/wallet_routes';
 
-import App from './components/ascribe_app';
+import AscribeApp from './components/ascribe_app';
 
 import PieceList from './components/piece_list';
 import PieceContainer from './components/ascribe_detail/piece_container';
@@ -29,7 +29,7 @@ import { ProxyHandler, AuthRedirect } from './components/ascribe_routes/proxy_ha
 
 
 const COMMON_ROUTES = (
-    <Route path='/' component={App}>
+    <Route path='/' component={AscribeApp}>
         <Route
             path='login'
             component={ProxyHandler(AuthRedirect({to: '/collection', when: 'loggedIn'}))(LoginContainer)} />