Avoid duplicate destroy on same thread (facebook#38233)

Summary:
Pull Request resolved: facebook#38233

When call ReactHost.destroy multiple times on same thread, the synchronization we have now can not protect us from concurrent issues such as ```ConcurrentModificationException```, to avoid this case this diff checks if ReactInstance has been reset, if so it means an early destroy has been called and we should not destroy again.

Changelog:
[Android][Changed] - Avoid duplicate destroy on same thread

Reviewed By: fkgozali

Differential Revision: D47276191

fbshipit-source-id: 2291b89cb980ca762abddb835e703abd095a93b3

Author: Lulu Wu

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/bridgeless/ReactHost.java

@@ -1415,6 +1415,13 @@ private void oldDestroy(String reason, @Nullable Exception ex) {
     raiseSoftException(method, reason, ex);
 
     synchronized (mReactInstanceTaskRef) {
+      // Prevent re-destroy when ReactInstance has been reset already, which could happen when
+      // calling destroy multiple times on the same thread
+      ReactInstance reactInstance = mReactInstanceTaskRef.get().getResult();
+      if (reactInstance == null) {
+        return;
+      }
+
       // Retain a reference to current ReactContext before de-referenced by mReactContextRef
       final ReactContext reactContext = getCurrentReactContext();