if quick call jumpTo the transitionQueue will be quit before handle a…

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Closes https://github.com/facebook/react-native/pull/8071

Differential Revision: D3453372

Pulled By: ericvicenti

fbshipit-source-id: 3494faee1a83574c3937a6545b246713ec38e0d0

Libraries/CustomComponents/Navigator/Navigator.js

@@ -373,7 +373,7 @@ var Navigator = React.createClass({
   },
 
   _transitionTo: function(destIndex, velocity, jumpSpringTo, cb) {
-    if (destIndex === this.state.presentedIndex) {
+    if (destIndex === this.state.presentedIndex && this.state.transitionQueue.length > 0) {
       return;
     }
     if (this.state.transitionFromIndex !== null) {