[tf.data] Remove a mechanism for mutating the state of iterator context (as it validates the invariant that IteratorContext is immutable once created).

PiperOrigin-RevId: 381564111
Change-Id: I4521378c7f22180b7ad6a393d9384ec4d78d69fc
diff --git a/tensorflow/core/framework/dataset.h b/tensorflow/core/framework/dataset.h
index 718134e..5be6f95 100644
--- a/tensorflow/core/framework/dataset.h
+++ b/tensorflow/core/framework/dataset.h
@@ -521,8 +521,6 @@
 
   thread::ThreadPoolInterface* thread_pool() { return params_.thread_pool; }
 
-  Params params() { return params_; }
-
   std::unique_ptr<thread::ThreadPool> CreateThreadPool(const string& name,
                                                        int num_threads) {
     if (params_.thread_pool) {