[es6] Perform the IsConstructor test in GetSuperConstructor.

src/compiler/js-generic-lowering.cc

Index: src/compiler/js-generic-lowering.cc
diff --git a/src/compiler/js-generic-lowering.cc b/src/compiler/js-generic-lowering.cc
index 1a8634db51006b6bb72e9efe774346bcc78a31c0..92001a6ad39afc4161b90dbc80999e4ab8046735 100644
--- a/src/compiler/js-generic-lowering.cc
+++ b/src/compiler/js-generic-lowering.cc
@@ -273,6 +273,12 @@ void JSGenericLowering::LowerJSDeleteProperty(Node* node) {
                                    : Runtime::kDeleteProperty_Sloppy);
 }
 
+void JSGenericLowering::LowerJSGetSuperConstructor(Node* node) {
+  CallDescriptor::Flags flags = FrameStateFlagForCall(node);
+  Callable callable = CodeFactory::GetSuperConstructor(isolate());
+  ReplaceWithStubCall(node, callable, flags);
+}
+
 void JSGenericLowering::LowerJSInstanceOf(Node* node) {
   CallDescriptor::Flags flags = FrameStateFlagForCall(node);
   Callable callable = CodeFactory::InstanceOf(isolate());