Move prototype metadata from internal properties to prototype maps

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index ba6800b04d496e437429f744addbc0c340aa5669..aabb0ed20d2274c212419ffbbd41a14cb0d61d0e 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -58,6 +58,9 @@ class Factory FINAL {
   // Create a new boxed value.
   Handle<Box> NewBox(Handle<Object> value);
 
+  // Create a new PrototypeInfo struct.
+  Handle<PrototypeInfo> NewPrototypeInfo(Handle<JSObject> prototype_obj);
+
   // Create a pre-tenured empty AccessorPair.
   Handle<AccessorPair> NewAccessorPair();