Remove the dependency of Zone on Isolate

src/compiler/verifier.cc

 // 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.
 
 #include "src/compiler/verifier.h"
 
 #include <algorithm>
 #include <deque>
 #include <queue>
 #include <sstream>
@@ skipping 811 matching lines @@
                "Node #%d:%s in B%d is not dominated by control input #%d:%s",
                node->id(), node->op()->mnemonic(), block->id(), ctl->id(),
                ctl->op()->mnemonic());
     }
   }
 }
 
 
 void ScheduleVerifier::Run(Schedule* schedule) {
   const size_t count = schedule->BasicBlockCount();
-  Zone tmp_zone(schedule->zone()->isolate());
+  Zone tmp_zone;
   Zone* zone = &tmp_zone;
   BasicBlock* start = schedule->start();
   BasicBlockVector* rpo_order = schedule->rpo_order();
 
   // Verify the RPO order contains only blocks from this schedule.
   CHECK_GE(count, rpo_order->size());
   for (BasicBlockVector::iterator b = rpo_order->begin(); b != rpo_order->end();
        ++b) {
     CHECK_EQ((*b), schedule->GetBlockById((*b)->id()));
     // All predecessors and successors should be in rpo and in this schedule.
@@ skipping 148 matching lines @@
     // Check inputs for all nodes in the block.
     for (size_t i = 0; i < block->NodeCount(); i++) {
       Node* node = block->NodeAt(i);
       CheckInputsDominate(schedule, block, node, static_cast<int>(i) - 1);
     }
   }
 }
 }
 }
 }  // namespace v8::internal::compiler