Auto create ApiLocalScope before calling native functions, this ensures that

runtime/bin/stdin.cc

 // Copyright (c) 2013, 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 "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/utils.h"
 #include "bin/stdin.h"
 
 #include "platform/globals.h"
 #include "platform/thread.h"
 #include "platform/utils.h"
 
 #include "include/dart_api.h"
 
 
 namespace dart {
 namespace bin {
 
 void FUNCTION_NAME(Stdin_ReadByte)(Dart_NativeArguments args) {
-  Dart_EnterScope();
   Dart_SetReturnValue(args, Dart_NewInteger(Stdin::ReadByte()));
-  Dart_ExitScope();
 }
 
 
 void FUNCTION_NAME(Stdin_SetEchoMode)(Dart_NativeArguments args) {
-  Dart_EnterScope();
   bool enabled = DartUtils::GetBooleanValue(Dart_GetNativeArgument(args, 1));
   Stdin::SetEchoMode(enabled);
   Dart_SetReturnValue(args, Dart_Null());
-  Dart_ExitScope();
 }
 
 
 void FUNCTION_NAME(Stdin_SetLineMode)(Dart_NativeArguments args) {
-  Dart_EnterScope();
   bool enabled = DartUtils::GetBooleanValue(Dart_GetNativeArgument(args, 1));
   Stdin::SetLineMode(enabled);
   Dart_SetReturnValue(args, Dart_Null());
-  Dart_ExitScope();
 }
 
 }  // namespace bin
 }  // namespace dart