Remove (now) unused GetPropertyWithHandler.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 27f93fdc26da944170122676a1929ef4ae6a1ea5..a15dfae55683ed76e1f1b491ba3049df01c299fd 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -4065,8 +4065,8 @@ Maybe<bool> Object::RedefineIncompatibleProperty(Isolate* isolate,
 
 
 Maybe<bool> Object::SetDataProperty(LookupIterator* it, Handle<Object> value) {
-  // Proxies are handled on the WithHandler path. Other non-JSObjects cannot
-  // have own properties.
+  // Proxies are handled elsewhere. Other non-JSObjects cannot have own
+  // properties.
   Handle<JSObject> receiver = Handle<JSObject>::cast(it->GetReceiver());
 
   // Store on the holder which may be hidden behind the receiver.