Limit the time d8 interactive shell's input strings stay alive.

src/d8.cc

 // Copyright 2011 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 846 matching lines @@
   if (chars == NULL) return Handle<String>();
   Handle<String> result = String::New(chars);
   delete[] chars;
   return result;
 }
 
 
 void Shell::RunShell() {
   Locker locker;
   Context::Scope context_scope(evaluation_context_);
-  HandleScope handle_scope;
+  HandleScope outer_scope;
   Handle<String> name = String::New("(d8)");
 #ifndef V8_SHARED
   LineEditor* editor = LineEditor::Get();
   printf("V8 version %s [console: %s]\n", V8::GetVersion(), editor->name());
   if (i::FLAG_debugger) {
     printf("JavaScript debugger enabled\n");
   }
   editor->Open();
   while (true) {
     i::SmartPointer<char> input = editor->Prompt(Shell::kPrompt);
     if (input.is_empty()) break;
     editor->AddHistory(*input);
+    HandleScope inner_scope;
     ExecuteString(String::New(*input), name, true, true);
   }
   editor->Close();
 #else
   printf("V8 version %s [D8 light using shared library]\n", V8::GetVersion());
   static const int kBufferSize = 256;
   while (true) {
     char buffer[kBufferSize];
     printf("%s", Shell::kPrompt);
     if (fgets(buffer, kBufferSize, stdin) == NULL) break;
+    HandleScope inner_scope;
     ExecuteString(String::New(buffer), name, true, true);
   }
 #endif  // V8_SHARED
   printf("\n");
 }
 
 
 #ifndef V8_SHARED
 class ShellThread : public i::Thread {
  public:
@@ skipping 396 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif