[turbofan] Remove locally constructed simplified builders.

src/compiler/js-intrinsic-lowering.cc

Index: src/compiler/js-intrinsic-lowering.cc
diff --git a/src/compiler/js-intrinsic-lowering.cc b/src/compiler/js-intrinsic-lowering.cc
index 219a452a7d66adc38770fe1bedd64739ea9e08bf..aeae0c60ca7db55250e4330761b7a24fa9c6b941 100644
--- a/src/compiler/js-intrinsic-lowering.cc
+++ b/src/compiler/js-intrinsic-lowering.cc
@@ -20,10 +20,7 @@ namespace compiler {
 
 JSIntrinsicLowering::JSIntrinsicLowering(Editor* editor, JSGraph* jsgraph,
                                          DeoptimizationMode mode)
-    : AdvancedReducer(editor),
-      jsgraph_(jsgraph),
-      mode_(mode),
-      simplified_(jsgraph->zone()) {}
+    : AdvancedReducer(editor), jsgraph_(jsgraph), mode_(mode) {}
 
 
 Reduction JSIntrinsicLowering::Reduce(Node* node) {
@@ -608,6 +605,11 @@ MachineOperatorBuilder* JSIntrinsicLowering::machine() const {
   return jsgraph()->machine();
 }
 
+
+SimplifiedOperatorBuilder* JSIntrinsicLowering::simplified() const {
+  return jsgraph()->simplified();
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8