[builtins] Properly optimize Object.prototype.isPrototypeOf.

src/compiler/js-call-reducer.h

Index: src/compiler/js-call-reducer.h
diff --git a/src/compiler/js-call-reducer.h b/src/compiler/js-call-reducer.h
index 7f57ed78b5e4da980813adc7804617669da7bef6..4a2bb30deb7c05cadbc4e6b99b1567fe8571a6b5 100644
--- a/src/compiler/js-call-reducer.h
+++ b/src/compiler/js-call-reducer.h
@@ -49,6 +49,7 @@ class JSCallReducer final : public AdvancedReducer {
   Reduction ReduceObjectGetPrototype(Node* node, Node* object);
   Reduction ReduceObjectGetPrototypeOf(Node* node);
   Reduction ReduceObjectPrototypeGetProto(Node* node);
+  Reduction ReduceObjectPrototypeIsPrototypeOf(Node* node);
   Reduction ReduceReflectGetPrototypeOf(Node* node);
   Reduction ReduceArrayForEach(Handle<JSFunction> function, Node* node);
   Reduction ReduceSpreadCall(Node* node, int arity);