Make AST graph builder parametric in context specialization.

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"
@@ skipping 56 matching lines @@
   CompilationInfo* info() const { return info_; }
   CommonOperatorBuilder* common() const { return jsgraph()->common(); }
   MachineOperatorBuilder* machine() const { return machine_; }
 
  private:
   CompilationInfo* info_;
   JSGraph* jsgraph_;
   Linkage* linkage_;
   MachineOperatorBuilder* machine_;
   SetOncePointer<Node> centrystub_constant_;
+
+  Node* LoadObjectField(Node* object, int offset, Node* effect);
 };
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_JS_GENERIC_LOWERING_H_