[builtins] Move StringLastIndexOf to a builtin.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 249513c93bf334f8348a0e217bb98324075d021c..9aa97b44cc836938f4f89bc5674fe3d8e8fcdb0b 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -9251,6 +9251,9 @@ class String: public Name {
   static int IndexOf(Isolate* isolate, Handle<String> sub, Handle<String> pat,
                      int start_index);
 
+  static Object* LastIndexOf(Isolate* isolate, Handle<Object> receiver,
+                             Handle<Object> pat, Handle<Object> position);
+

[Franzi, 2016/09/19 08:04:21]

I don't like pat as variable name (even thought the JS function was using the
same). Can we use search_string or string?

   // String equality operations.
   inline bool Equals(String* other);
   inline static bool Equals(Handle<String> one, Handle<String> two);