Track ascii-ness of data in externalized strings.

src/bootstrapper.cc

 // Copyright 2006-2008 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 1444 matching lines @@
   }
   // Install auto extensions.
   current = v8::RegisteredExtension::first_extension();
   while (current != NULL) {
     if (current->extension()->auto_enable())
       InstallExtension(current);
     current = current->next();
   }
 
   if (FLAG_expose_gc) InstallExtension("v8/gc");
+  if (FLAG_expose_externalize_string) InstallExtension("v8/externalize");
 
   if (extensions == NULL) return true;
   // Install required extensions
   int count = v8::ImplementationUtilities::GetNameCount(extensions);
   const char** names = v8::ImplementationUtilities::GetNames(extensions);
   for (int i = 0; i < count; i++) {
     if (!InstallExtension(names[i]))
       return false;
   }
 
@@ skipping 331 matching lines @@
 }
 
 
 // Restore statics that are thread local.
 char* BootstrapperActive::RestoreState(char* from) {
   nesting_ = *reinterpret_cast<int*>(from);
   return from + sizeof(nesting_);
 }
 
 } }  // namespace v8::internal