[turbofan] remove graph from InstructionSequence

src/compiler/instruction-selector.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_INSTRUCTION_SELECTOR_H_
 #define V8_COMPILER_INSTRUCTION_SELECTOR_H_
 
 #include <deque>
 
 #include "src/compiler/common-operator.h"
@@ skipping 175 matching lines @@
   void VisitCall(Node* call, BasicBlock* continuation,
                  BasicBlock* deoptimization);
   void VisitGoto(BasicBlock* target);
   void VisitBranch(Node* input, BasicBlock* tbranch, BasicBlock* fbranch);
   void VisitReturn(Node* value);
   void VisitThrow(Node* value);
   void VisitDeoptimize(Node* deopt);
 
   // ===========================================================================
 
-  Graph* graph() const { return sequence()->graph(); }
   Linkage* linkage() const { return sequence()->linkage(); }
   Schedule* schedule() const { return sequence()->schedule(); }
   InstructionSequence* sequence() const { return sequence_; }
   Zone* instruction_zone() const { return sequence()->zone(); }
   Zone* zone() { return &zone_; }
 
   // ===========================================================================
 
   Zone zone_;
   InstructionSequence* sequence_;
   SourcePositionTable* source_positions_;
   Features features_;
   BasicBlock* current_block_;
   ZoneDeque<Instruction*> instructions_;
   BoolVector defined_;
   BoolVector used_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_INSTRUCTION_SELECTOR_H_