Add support for enabling DCHECKs in release mode

src/compiler/scheduler.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 <deque>
 #include <queue>
 
 #include "src/compiler/scheduler.h"
 
 #include "src/bit-vector.h"
@@ skipping 1193 matching lines @@
     if (block->dominator_depth() > data->minimum_block_->dominator_depth()) {
       data->minimum_block_ = block;
       queue_.push(node);
       Trace("Propagating #%d:%s minimum_block = B%d, dominator_depth = %d\n",
             node->id(), node->op()->mnemonic(),
             data->minimum_block_->id().ToInt(),
             data->minimum_block_->dominator_depth());
     }
   }
 
-#if DEBUG
+#if DCHECK_IS_ON
   bool InsideSameDominatorChain(BasicBlock* b1, BasicBlock* b2) {
     BasicBlock* dominator = scheduler_->GetCommonDominator(b1, b2);
     return dominator == b1 || dominator == b2;
   }
 #endif
 
   Scheduler* scheduler_;
   Schedule* schedule_;
   ZoneQueue<Node*> queue_;
 };
@@ skipping 267 matching lines @@
   for (NodeVectorIter i = nodes->begin(); i != nodes->end(); ++i) {
     schedule_->SetBlockForNode(to, *i);
     scheduled_nodes_[to->id().ToSize()].push_back(*i);
   }
   nodes->clear();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8