Fix build because of dead fields.

src/compiler/graph-visualizer.cc

 // Copyright 2013 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.
 
 #include "src/compiler/graph-visualizer.h"
 
 #include <sstream>
 #include <string>
 
 #include "src/code-stubs.h"
@@ skipping 201 matching lines @@
   JSONGraphNodeWriter(os, &tmp_zone, &ad.graph).Print();
   os << "],\"edges\":[";
   JSONGraphEdgeWriter(os, &tmp_zone, &ad.graph).Print();
   os << "]}";
   return os;
 }
 
 
 class GraphVisualizer {
  public:
-  GraphVisualizer(std::ostream& os, Zone* zone, const Graph* graph);  // NOLINT
+  GraphVisualizer(std::ostream& os, Zone* zone, const Graph* graph)
+      : all_(zone, graph), os_(os) {}
 
   void Print();
 
   void PrintNode(Node* node, bool gray);
 
  private:
   void PrintEdge(Node::Edge edge);
 
-  Zone* zone_;
   AllNodes all_;
   std::ostream& os_;
-  const Graph* const graph_;
 
   DISALLOW_COPY_AND_ASSIGN(GraphVisualizer);
 };
 
 
 static Node* GetControlCluster(Node* node) {
   if (OperatorProperties::IsBasicBlockBegin(node->op())) {
     return node;
   } else if (node->op()->ControlInputCount() == 1) {
     Node* control = NodeProperties::GetControlInput(node, 0);
@@ skipping 138 matching lines @@
   // With all the nodes written, add the edges.
   for (Node* const node : all_.live) {
     for (UseIter i = node->uses().begin(); i != node->uses().end(); ++i) {
       PrintEdge(i.edge());
     }
   }
   os_ << "}\n";
 }
 
 
-GraphVisualizer::GraphVisualizer(std::ostream& os, Zone* zone,
-                                 const Graph* graph)  // NOLINT
-    : zone_(zone),
-      all_(zone, graph),
-      os_(os),
-      graph_(graph) {}
-
-
 std::ostream& operator<<(std::ostream& os, const AsDOT& ad) {
   Zone tmp_zone(ad.graph.zone()->isolate());
   GraphVisualizer(os, &tmp_zone, &ad.graph).Print();
   return os;
 }
 
 
 class GraphC1Visualizer {
  public:
   GraphC1Visualizer(std::ostream& os, Zone* zone);  // NOLINT
@@ skipping 377 matching lines @@
 
 
 std::ostream& operator<<(std::ostream& os, const AsC1VAllocator& ac) {
   Zone tmp_zone(ac.allocator_->code()->zone()->isolate());
   GraphC1Visualizer(os, &tmp_zone).PrintAllocator(ac.phase_, ac.allocator_);
   return os;
 }
 }
 }
 }  // namespace v8::internal::compiler