Don't EnsureHasInitialMap on non-constructors

src/compiler/js-typed-lowering.cc

Index: src/compiler/js-typed-lowering.cc
diff --git a/src/compiler/js-typed-lowering.cc b/src/compiler/js-typed-lowering.cc
index 883219d47037d800acff6a80089933324fc9b49a..ba7eb083eb9762967d8179068b650b24fe866447 100644
--- a/src/compiler/js-typed-lowering.cc
+++ b/src/compiler/js-typed-lowering.cc
@@ -1120,7 +1120,8 @@ Reduction JSTypedLowering::ReduceJSInstanceOf(Node* node) {
     Handle<JSFunction> function =
         Handle<JSFunction>::cast(r.right_type()->AsConstant()->Value());
     Handle<SharedFunctionInfo> shared(function->shared(), isolate());
-    if (!function->map()->has_non_instance_prototype()) {
+    if (function->IsConstructor() &&
+        !function->map()->has_non_instance_prototype()) {
       JSFunction::EnsureHasInitialMap(function);
       DCHECK(function->has_initial_map());
       Handle<Map> initial_map(function->initial_map(), isolate());