[fixed] Support LinkContainer without history

Author: cwbuecheler

src/LinkContainer.js

@@ -31,11 +31,17 @@ export default class LinkContainer extends React.Component {
     delete props.state;
 
     props.onClick = this.onClick;
-    props.href = history.createHref(to, query);
-    if (hash) {
-      props.href += hash;
+
+    // Ignore if rendered outside the context of history, simplifies unit testing.
+    if (history) {
+      props.href = history.createHref(to, query);
+
+      if (hash) {
+        props.href += hash;
+      }
+
+      props.active = history.isActive(to, query, onlyActiveOnIndex);
     }
-    props.active = history.isActive(to, query, onlyActiveOnIndex);
 
     return React.cloneElement(React.Children.only(children), props);
   }
@@ -53,7 +59,7 @@ LinkContainer.propTypes = {
 };
 
 LinkContainer.contextTypes = {
-  history: React.PropTypes.object.isRequired
+  history: React.PropTypes.object
 };
 
 LinkContainer.defaultProps = {