[turbofan] Move SimplifiedOperatorBuilder into JSGraph.

test/cctest/compiler/test-changes-lowering.cc

Index: test/cctest/compiler/test-changes-lowering.cc
diff --git a/test/cctest/compiler/test-changes-lowering.cc b/test/cctest/compiler/test-changes-lowering.cc
index b6b48bdac4f453a60fd7b6cb69b26fc5e3944e6c..43ea21f3a1fd8cd705506e99ce2fa8d2603db438 100644
--- a/test/cctest/compiler/test-changes-lowering.cc
+++ b/test/cctest/compiler/test-changes-lowering.cc
@@ -34,7 +34,7 @@ class ChangesLoweringTester : public GraphBuilderTester<ReturnType> {
       : GraphBuilderTester<ReturnType>(p0),
         javascript(this->zone()),
         jsgraph(this->isolate(), this->graph(), this->common(), &javascript,
-                this->machine()),
+                nullptr, this->machine()),
         function(Handle<JSFunction>::null()) {}
 
   JSOperatorBuilder javascript;