Allow embedding of ConsString objects into code.

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index b91b246c70f9074977df0eb7abb32e4771a6b3aa..4dd1974fcddb198e373f5d5cf04af18afd5ccd32 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -197,10 +197,6 @@ class Factory V8_FINAL {
   MUST_USE_RESULT MaybeHandle<String> NewConsString(Handle<String> left,
                                                     Handle<String> right);
 
-  // Create a new sequential string containing the concatenation of the inputs.
-  Handle<String> NewFlatConcatString(Handle<String> first,
-                                     Handle<String> second);
-
   // Create a new string object which holds a proper substring of a string.
   Handle<String> NewProperSubString(Handle<String> str,
                                     int begin,