Fix for issue 4808 (The vm crashes when parseInt is called with string containing a $).

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"
@@ skipping 86 matching lines @@
     *is_positive = tokens[0].kind == Token::kTIGHTADD;
     *value = tokens[1].literal;
     return true;
   }
   return false;
 }
 
 
 DEFINE_NATIVE_ENTRY(MathNatives_parseInt, 1) {
   GET_NATIVE_ARGUMENT(String, value, arguments->At(0));
-  Scanner scanner(value, String::Handle());
+  const String& dummy_key = String::Handle(Symbols::Empty());
+  Scanner scanner(value, dummy_key);
   const Scanner::GrowableTokenStream& tokens = scanner.GetStream();
   String* int_string;
   bool is_positive;
   if (IsValidLiteral(tokens, Token::kINTEGER, &is_positive, &int_string)) {
     if (is_positive) {
       return Integer::New(*int_string);
     } else {
       String& temp = String::Handle();
       temp = String::Concat(String::Handle(Symbols::New("-")),
                             *int_string);
       return Integer::New(temp);
     }
   } else {
     GrowableArray<const Object*> args;
     args.Add(&value);
     Exceptions::ThrowByType(Exceptions::kFormat, args);
     return Object::null();
   }
 }
 
 
 DEFINE_NATIVE_ENTRY(MathNatives_parseDouble, 1) {
   GET_NATIVE_ARGUMENT(String, value, arguments->At(0));
-  Scanner scanner(value, String::Handle());
+  const String& dummy_key = String::Handle(Symbols::Empty());
+  Scanner scanner(value, dummy_key);
   const Scanner::GrowableTokenStream& tokens = scanner.GetStream();
   String* number_string;
   bool is_positive;
   if (IsValidLiteral(tokens, Token::kDOUBLE, &is_positive, &number_string)) {
     const char* cstr = number_string->ToCString();
     char* p_end = NULL;
     double double_value = strtod(cstr, &p_end);
     ASSERT(p_end != cstr);
     if (!is_positive) {
       double_value = -double_value;
@@ skipping 24 matching lines @@
     }
   }
 
   GrowableArray<const Object*> args;
   args.Add(&value);
   Exceptions::ThrowByType(Exceptions::kFormat, args);
   return Object::null();
 }
 
 }  // namespace dart