remove outdated code in RCTNavigator

Reviewed By: mmmulani

Differential Revision: D4095285

fbshipit-source-id: 1e2111b6647e14562675e4474cd56acb91d22ec2

React/Views/RCTNavigator.h

@@ -15,7 +15,6 @@
 
 @interface RCTNavigator : UIView <RCTFrameUpdateObserver>
 
-@property (nonatomic, strong) UIView *reactNavSuperviewLink;
 @property (nonatomic, assign) NSInteger requestedTopOfStack;
 @property (nonatomic, assign) BOOL interactivePopGestureEnabled;
 

React/Views/RCTNavigator.m

@@ -499,17 +499,6 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithCoder:(NSCoder *)aDecoder)
   [_bridge.eventDispatcher sendFakeScrollEvent:self.reactTag];
 }
 
-/**
- * Must be overridden because UIKit removes the view's superview when used
- * as a navigator - it's considered outside the view hierarchy.
- */
-- (UIView *)reactSuperview
-{
-  RCTAssert(!_bridge.isValid || self.superview != nil, @"put reactNavSuperviewLink back");
-  UIView *superview = [super reactSuperview];
-  return superview ?: self.reactNavSuperviewLink;
-}
-
 - (void)reactBridgeDidFinishTransaction
 {
   // we can't hook up the VC hierarchy in 'init' because the subviews aren't