Handlify LookupSingleCharacterStringFromCode.

src/handles.h

Index: src/handles.h
diff --git a/src/handles.h b/src/handles.h
index 3f6040421220fb064f4ce3180c95ae8f31074dbd..edeb27b5106c02edbf73d8c82e3a129293c4f832 100644
--- a/src/handles.h
+++ b/src/handles.h
@@ -302,9 +302,6 @@ Handle<Object> HasProperty(Handle<JSReceiver> obj, Handle<Object> key);
 
 Handle<Object> GetProperty(Handle<JSReceiver> obj, const char* name);
 
-Handle<String> LookupSingleCharacterStringFromCode(Isolate* isolate,
-                                                   uint32_t index);
-
 // Get the JS object corresponding to the given script; create it
 // if none exists.
 Handle<JSValue> GetScriptWrapper(Handle<Script> script);