Use dot_for_symbol.

src/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2825 matching lines @@
         //   <let x' be a temporary variable>
         //   for (x' in e) {
         //     let x;
         //     x = x';
         //     b;
         //   }
 
         // TODO(keuchel): Move the temporary variable to the block scope, after
         // implementing stack allocated block scoped variables.
         Factory* heap_factory = isolate()->factory();
-        Handle<String> dot =
-            heap_factory->NewStringFromAscii(CStrVector(".for."));
-        Handle<String> tempstr = heap_factory->NewConsString(dot, name);
+        Handle<String> tempstr =
+            heap_factory->NewConsString(heap_factory->dot_for_symbol(), name);
         Handle<String> tempname = heap_factory->LookupSymbol(tempstr);
         Variable* temp = top_scope_->DeclarationScope()->NewTemporary(tempname);
         VariableProxy* temp_proxy = factory()->NewVariableProxy(temp);
         ForInStatement* loop = factory()->NewForInStatement(labels);
         Target target(&this->target_stack_, loop);
 
         // The expression does not see the loop variable.
         Expect(Token::IN, CHECK_OK);
         top_scope_ = saved_scope;
         Expression* enumerable = ParseExpression(true, CHECK_OK);
@@ skipping 3122 matching lines @@
       ASSERT(info->isolate()->has_pending_exception());
     } else {
       result = parser.ParseProgram();
     }
   }
   info->SetFunction(result);
   return (result != NULL);
 }
 
 } }  // namespace v8::internal