Add support for enabling DCHECKs in release mode

src/parser.h

 // Copyright 2012 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_PARSER_H_
 #define V8_PARSER_H_
 
 #include "src/allocation.h"
 #include "src/ast.h"
 #include "src/compiler.h"  // For CachedDataMode
@@ skipping 189 matching lines @@
   void FlushText();
   void FlushTerms();
   Zone* zone() const { return zone_; }
 
   Zone* zone_;
   bool pending_empty_;
   ZoneList<uc16>* characters_;
   BufferedZoneList<RegExpTree, 2> terms_;
   BufferedZoneList<RegExpTree, 2> text_;
   BufferedZoneList<RegExpTree, 2> alternatives_;
-#ifdef DEBUG
+#if DCHECK_IS_ON
   enum {ADD_NONE, ADD_CHAR, ADD_TERM, ADD_ASSERT, ADD_ATOM} last_added_;
 #define LAST(x) last_added_ = x;
 #else
 #define LAST(x)
 #endif
 };
 
 
 class RegExpParser BASE_EMBEDDED {
  public:
@@ skipping 777 matching lines @@
 }
 
 
 Expression* ParserTraits::CloseTemplateLiteral(TemplateLiteralState* state,
                                                int start, Expression* tag) {
   return parser_->CloseTemplateLiteral(state, start, tag);
 }
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_