Fixed crash in [UIManager setLocalData:]

Summary:
This is pretty normal and harmless case, we should not crash here.
I plan to refactor similar places in this file soon.

Reviewed By: AaaChiuuu

Differential Revision: D5983443

fbshipit-source-id: 922fea8ed12ebef45d249f16739aa81fe3254f19

React/Modules/RCTUIManager.m

@@ -317,7 +317,10 @@ - (void)setLocalData:(NSObject *)localData forView:(UIView *)view
 
   RCTExecuteOnUIManagerQueue(^{
     RCTShadowView *shadowView = self->_shadowViewRegistry[tag];
-    RCTAssert(shadowView != nil, @"Could not locate shadow view with tag #%@", tag);
+    if (shadowView == nil) {
+      RCTLogWarn(@"Could not locate shadow view with tag #%@, this is probably caused by a temporary inconsistency between native views and shadow views.", tag);
+      return;
+    }
 
     shadowView.localData = localData;
     [self setNeedsLayout];