[turbofan] Introduce LoadFunctionPrototype simplified operator.

src/compiler/access-info.h

Index: src/compiler/access-info.h
diff --git a/src/compiler/access-info.h b/src/compiler/access-info.h
index 1d485dd0d4cf1a14a4aa1bc92fc181f7a549808d..285657e8d4790722f7e5a15769364e7ad1fc14b9 100644
--- a/src/compiler/access-info.h
+++ b/src/compiler/access-info.h
@@ -62,6 +62,7 @@ class PropertyAccessInfo final {
     kDataConstant,
     kDataField,
     kAccessorConstant,
+    kFunctionPrototype,
     kGeneric
   };
 
@@ -79,6 +80,7 @@ class PropertyAccessInfo final {
   static PropertyAccessInfo AccessorConstant(MapList const& receiver_maps,
                                              Handle<Object> constant,
                                              MaybeHandle<JSObject> holder);
+  static PropertyAccessInfo FunctionPrototype(MapList const& receiver_maps);
   static PropertyAccessInfo Generic(MapList const& receiver_maps);
 
   PropertyAccessInfo();
@@ -89,6 +91,7 @@ class PropertyAccessInfo final {
   bool IsDataConstant() const { return kind() == kDataConstant; }
   bool IsDataField() const { return kind() == kDataField; }
   bool IsAccessorConstant() const { return kind() == kAccessorConstant; }
+  bool IsFunctionPrototype() const { return kind() == kFunctionPrototype; }
   bool IsGeneric() const { return kind() == kGeneric; }
 
   bool HasTransitionMap() const { return !transition_map().is_null(); }