Create frequently used symbols in the vm isolate

lib/math.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include <ctype.h>  // isspace.
 
 #include "vm/bootstrap_natives.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/random.h"
 #include "vm/scanner.h"
+#include "vm/symbols.h"
 
 namespace dart {
 
 DEFINE_NATIVE_ENTRY(MathNatives_sqrt, 1) {
   GET_NATIVE_ARGUMENT(Double, operand, arguments->At(0));
   arguments->SetReturn(Double::Handle(Double::New(sqrt(operand.value()))));
 }
 
 DEFINE_NATIVE_ENTRY(MathNatives_sin, 1) {
   GET_NATIVE_ARGUMENT(Double, operand, arguments->At(0));
@@ skipping 85 matching lines @@
   Scanner scanner(value, String::Handle());
   const Scanner::GrowableTokenStream& tokens = scanner.GetStream();
   String* int_string;
   bool is_positive;
   if (IsValidLiteral(tokens, Token::kINTEGER, &is_positive, &int_string)) {
     Integer& result = Integer::Handle();
     if (is_positive) {
       result = Integer::New(*int_string);
     } else {
       String& temp = String::Handle();
-      temp = String::Concat(String::Handle(String::NewSymbol("-")),
+      temp = String::Concat(String::Handle(Symbols::New("-")),
                             *int_string);
       result = Integer::New(temp);
     }
     arguments->SetReturn(result);
   } else {
     GrowableArray<const Object*> args;
     args.Add(&value);
     Exceptions::ThrowByType(Exceptions::kBadNumberFormat, args);
   }
 }
@@ skipping 43 matching lines @@
       return;
     }
   }
 
   GrowableArray<const Object*> args;
   args.Add(&value);
   Exceptions::ThrowByType(Exceptions::kBadNumberFormat, args);
 }
 
 }  // namespace dart