[es6] Remove left-overs from Function.prototype.toMethod.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 3e88c961eef0756bc54e58bbae3d0a2076beebd2..02d8d3481f636d0b90702251b59684cde3eb8861 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -10134,30 +10134,6 @@ void JSFunction::AttemptConcurrentOptimization() {
 }
 
 
-Handle<JSFunction> JSFunction::CloneClosure(Handle<JSFunction> function) {
-  Isolate* isolate = function->GetIsolate();
-  Handle<Map> map(function->map());
-  Handle<SharedFunctionInfo> shared(function->shared());
-  Handle<Context> context(function->context());
-  Handle<JSFunction> clone =
-      isolate->factory()->NewFunctionFromSharedFunctionInfo(shared, context);
-
-  if (shared->bound()) {
-    clone->set_function_bindings(function->function_bindings());
-  }
-
-  // In typical case, __proto__ of ``function`` is the default Function
-  // prototype, which means that SetPrototype below is a no-op.
-  // In rare cases when that is not true, we mutate the clone's __proto__.
-  Handle<Object> original_prototype(map->prototype(), isolate);
-  if (*original_prototype != clone->map()->prototype()) {
-    JSObject::SetPrototype(clone, original_prototype, false).Assert();
-  }
-
-  return clone;
-}
-
-
 void SharedFunctionInfo::AddSharedCodeToOptimizedCodeMap(
     Handle<SharedFunctionInfo> shared, Handle<Code> code) {
   Isolate* isolate = shared->GetIsolate();