[turbofan] Remove the EmptyFrameState caching on JSGraph.

test/unittests/compiler/js-intrinsic-lowering-unittest.cc

Index: test/unittests/compiler/js-intrinsic-lowering-unittest.cc
diff --git a/test/unittests/compiler/js-intrinsic-lowering-unittest.cc b/test/unittests/compiler/js-intrinsic-lowering-unittest.cc
index 7c2f45942ce0893834233eb5ba7f8dafe4af988e..6e5f99e89a2ddb8279b7d1ae8e2b12868349127e 100644
--- a/test/unittests/compiler/js-intrinsic-lowering-unittest.cc
+++ b/test/unittests/compiler/js-intrinsic-lowering-unittest.cc
@@ -43,13 +43,6 @@ class JSIntrinsicLoweringTest : public GraphTest {
     return reducer.Reduce(node);
   }
 
-  Node* EmptyFrameState() {
-    MachineOperatorBuilder machine(zone());
-    JSGraph jsgraph(isolate(), graph(), common(), javascript(), nullptr,
-                    &machine);
-    return jsgraph.EmptyFrameState();
-  }
-
   JSOperatorBuilder* javascript() { return &javascript_; }
 
  private: