Add warning to protect against refactor hazard

The hook queue does not have resuming or "captured" updates, but if
we ever add them in the future, we'll need to make sure we check if the
queue is forked before transfering the pending updates to them.

packages/react-reconciler/src/ReactFiberHooks.js

@@ -683,6 +683,16 @@ function updateReducer<S, I, A>(
       baseQueue.next = pendingFirst;
       pendingQueue.next = baseFirst;
     }
+    if (__DEV__) {
+      if (current.baseQueue !== baseQueue) {
+        // Internal invariant that should never happen, but feasibly could in
+        // the future if we implement resuming, or some form of that.
+        console.error(
+          'Internal error: Expected work-in-progress queue to be a clone. ' +
+            'This is a bug in React.',
+        );
+      }
+    }
     current.baseQueue = baseQueue = pendingQueue;
     queue.pending = null;
   }