Verify a bit more about external strings

src/heap/heap-inl.h

Index: src/heap/heap-inl.h
diff --git a/src/heap/heap-inl.h b/src/heap/heap-inl.h
index b170e04798eaf4bba8d86db01e723337b02f1cb1..0dd10780a19692bdd77f8942d2464af8d784d1be 100644
--- a/src/heap/heap-inl.h
+++ b/src/heap/heap-inl.h
@@ -287,21 +287,6 @@ void Heap::PrintAlloctionsHash() {
 }
 
 
-void Heap::FinalizeExternalString(String* string) {
-  DCHECK(string->IsExternalString());
-  v8::String::ExternalStringResourceBase** resource_addr =
-      reinterpret_cast<v8::String::ExternalStringResourceBase**>(
-          reinterpret_cast<byte*>(string) + ExternalString::kResourceOffset -
-          kHeapObjectTag);
-
-  // Dispose of the C++ object if it has not already been disposed.
-  if (*resource_addr != NULL) {
-    (*resource_addr)->Dispose();
-    *resource_addr = NULL;
-  }
-}
-
-
 bool Heap::InNewSpace(Object* object) {
   bool result = new_space_.Contains(object);
   DCHECK(!result ||                 // Either not in new space