[turbofan] Remove the JSGraph dependency from the ControlFlowOptimizer.

test/unittests/compiler/graph-unittest.h

Index: test/unittests/compiler/graph-unittest.h
diff --git a/test/unittests/compiler/graph-unittest.h b/test/unittests/compiler/graph-unittest.h
index c905f30c6aee9946598e174f934a461eae9b153d..2318fa61f83c5d47419da729859fe478155a62fb 100644
--- a/test/unittests/compiler/graph-unittest.h
+++ b/test/unittests/compiler/graph-unittest.h
@@ -50,6 +50,8 @@ class GraphTest : public TestWithContext, public TestWithIsolateAndZone {
   Node* TrueConstant();
   Node* UndefinedConstant();
 
+  Node* EmptyFrameState();
+
   Matcher<Node*> IsFalseConstant();
   Matcher<Node*> IsTrueConstant();
   Matcher<Node*> IsUndefinedConstant();