[turbofan] Use graph assembler for memory optimizer.

src/compiler/memory-optimizer.h

 // Copyright 2016 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_MEMORY_OPTIMIZER_H_
 #define V8_COMPILER_MEMORY_OPTIMIZER_H_
 
+#include "src/compiler/graph-assembler.h"
 #include "src/zone/zone-containers.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Forward declarations.
 class CommonOperatorBuilder;
 struct ElementAccess;
 class Graph;
@@ skipping 106 matching lines @@
   void EnqueueUses(Node*, AllocationState const*);
   void EnqueueUse(Node*, int, AllocationState const*);
 
   AllocationState const* empty_state() const { return empty_state_; }
   Graph* graph() const;
   Isolate* isolate() const;
   JSGraph* jsgraph() const { return jsgraph_; }
   CommonOperatorBuilder* common() const;
   MachineOperatorBuilder* machine() const;
   Zone* zone() const { return zone_; }
+  GraphAssembler* gasm() { return &graph_assembler_; }
 
   SetOncePointer<const Operator> allocate_operator_;
   JSGraph* const jsgraph_;
   AllocationState const* const empty_state_;
   ZoneMap<NodeId, AllocationStates> pending_;
   ZoneQueue<Token> tokens_;
   Zone* const zone_;
+  GraphAssembler graph_assembler_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(MemoryOptimizer);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_MEMORY_OPTIMIZER_H_