stop wanring about using `onWillFocus` and `onDidFocus`.

Reviewed By: chaceliang

Differential Revision: D2925643

fb-gh-sync-id: d12b774b5c43d5369e2c02832d80541b2534fba6
shipit-source-id: d12b774b5c43d5369e2c02832d80541b2534fba6

Libraries/CustomComponents/Navigator/Navigator.js

@@ -227,19 +227,13 @@ var Navigator = React.createClass({
     /**
      * Will emit the target route upon mounting and before each nav transition
      */
-    onWillFocus: deprecatedPropType(
-      PropTypes.func,
-      "Use `navigationContext.addListener('willfocus', callback)` instead."
-    ),
+    onWillFocus: PropTypes.func,
 
     /**
      * Will be called with the new route of each scene after the transition is
      * complete or after the initial mounting
      */
-    onDidFocus: deprecatedPropType(
-      PropTypes.func,
-      "Use `navigationContext.addListener('didfocus', callback)` instead."
-    ),
+    onDidFocus: PropTypes.func,
 
     /**
      * Optionally provide a navigation bar that persists across scene