Fix stale scene cleanup

Summary: Previously we would not re-compute `this._transitionProps` after cleaning up stale scenes, so the render caused by setState still had the stale scenes in the props

Reviewed By: hedgerwang

Differential Revision: D3471011

fbshipit-source-id: fd08ef7a21355a229e877c85f06d6584eb44f38e

Libraries/NavigationExperimental/NavigationTransitioner.js

@@ -202,8 +202,14 @@ class NavigationTransitioner extends React.Component<any, Props, State> {
     const prevTransitionProps = this._prevTransitionProps;
     this._prevTransitionProps = null;
 
-    const scenes = this.state.scenes.filter(isSceneNotStale);
-    this.setState({ scenes });
+    const nextState = {
+      ...this.state,
+      scenes: this.state.scenes.filter(isSceneNotStale),
+    };
+
+    this._transitionProps = buildTransitionProps(this.props, nextState);
+
+    this.setState(nextState);
 
     this.props.onTransitionEnd && this.props.onTransitionEnd(
       this._transitionProps,