Fix shared library build.

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index bb4abb0e59ef8470c707b51b7a882d8c4e05b377..35d1a5914c5323e3ef2c5ec1221081fdb9e097b3 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -1036,9 +1036,7 @@ Handle<Value> Shell::ReadBinary(const Arguments& args) {
   // We skip checking the string for UTF8 characters and use it raw as
   // backing store for the external string with 8-bit characters.
   BinaryResource* resource = new BinaryResource(chars, size);
-  i::Handle<i::String> string(
-      FACTORY->NewExternalStringFromAscii(resource));
-  return Utils::ToLocal(string);
+  return String::NewExternal(resource);
 }