[turbofan] Some javascript operators are globally shared singletons.

src/compiler/js-generic-lowering.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_JS_GENERIC_LOWERING_H_
 #define V8_COMPILER_JS_GENERIC_LOWERING_H_
 
-#include "src/v8.h"
-
 #include "src/allocation.h"
 #include "src/code-factory.h"
 #include "src/compiler/graph.h"
 #include "src/compiler/graph-reducer.h"
 #include "src/compiler/js-graph.h"
+#include "src/compiler/linkage.h"
 #include "src/compiler/opcodes.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Forward declarations.
 class CommonOperatorBuilder;
 class MachineOperatorBuilder;
 class Linkage;
@@ skipping 43 matching lines @@
   JSGraph* jsgraph_;
   Linkage* linkage_;
   SetOncePointer<Node> centrystub_constant_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_JS_GENERIC_LOWERING_H_