Enter and Exit scope when calling into the native library tag handler

runtime/vm/bootstrap.cc

 // Copyright (c) 2012, 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 "vm/bootstrap.h"
 
 #include "include/dart_api.h"
 
 #include "vm/bootstrap_natives.h"
 #include "vm/compiler.h"
@@ skipping 238 matching lines @@
   String& source = String::Handle();
   Script& script = Script::Handle();
   Library& lib = Library::Handle();
   Error& error = Error::Handle();
   Dart_LibraryTagHandler saved_tag_handler = isolate->library_tag_handler();
 
   // Set the library tag handler for the isolate to the bootstrap
   // library tag handler so that we can load all the bootstrap libraries.
   isolate->set_library_tag_handler(BootstrapLibraryTagHandler);
 
-  // Enter the Dart Scope as we will be calling back into the library
-  // tag handler when compiling the bootstrap libraries.
-  Dart_EnterScope();
+  HANDLESCOPE(isolate);
 
   // Create library objects for all the bootstrap libraries.
   for (intptr_t i = 0;
        bootstrap_libraries[i].index_ != ObjectStore::kNone;
        ++i) {
     uri = Symbols::New(bootstrap_libraries[i].uri_);
     lib = Library::LookupLibrary(uri);
     if (lib.IsNull()) {
       lib = Library::NewLibraryHelper(uri, false);
       lib.Register();
@@ skipping 30 matching lines @@
                              bootstrap_libraries[i].patch_paths_);
       if (!error.IsNull()) {
         break;
       }
     }
   }
   if (error.IsNull()) {
     SetupNativeResolver();
   }
 
-  // Exit the Dart scope.
-  Dart_ExitScope();
-
   // Restore the library tag handler for the isolate.
   isolate->set_library_tag_handler(saved_tag_handler);
 
   return error.raw();
 }
 
 }  // namespace dart