Added handling of empty handles to String::AsciiValue and String::Value.

src/api.cc

 // Copyright 2007-2008 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 2631 matching lines @@
 }
 
 
 String::Utf8Value::~Utf8Value() {
   i::DeleteArray(str_);
 }
 
 
 String::AsciiValue::AsciiValue(v8::Handle<v8::Value> obj) {
   EnsureInitialized("v8::String::AsciiValue::AsciiValue()");
+  if (obj.IsEmpty()) {
+    str_ = NULL;
+    length_ = 0;
+    return;
+  }
   HandleScope scope;
   TryCatch try_catch;
   Handle<String> str = obj->ToString();
   if (str.IsEmpty()) {
     str_ = NULL;
     length_ = 0;
   } else {
     length_ = str->Length();
     str_ = i::NewArray<char>(length_ + 1);
     str->WriteAscii(str_);
   }
 }
 
 
 String::AsciiValue::~AsciiValue() {
   i::DeleteArray(str_);
 }
 
 
 String::Value::Value(v8::Handle<v8::Value> obj) {
   EnsureInitialized("v8::String::Value::Value()");
+  if (obj.IsEmpty()) {
+    str_ = NULL;
+    length_ = 0;
+    return;
+  }
   HandleScope scope;
   TryCatch try_catch;
   Handle<String> str = obj->ToString();
   if (str.IsEmpty()) {
     str_ = NULL;
     length_ = 0;
   } else {
     length_ = str->Length();
     str_ = i::NewArray<uint16_t>(length_ + 1);
     str->Write(str_);
@@ skipping 243 matching lines @@
       reinterpret_cast<HandleScopeImplementer*>(storage);
   List<void**>* blocks_of_archived_thread = thread_local->Blocks();
   ImplementationUtilities::HandleScopeData* handle_data_of_archived_thread =
       &thread_local->handle_scope_data_;
   Iterate(v, blocks_of_archived_thread, handle_data_of_archived_thread);
 
   return storage + ArchiveSpacePerThread();
 }
 
 } }  // namespace v8::internal