[runtime][ic] Constant field tracking support.

src/lookup.h

Index: src/lookup.h
diff --git a/src/lookup.h b/src/lookup.h
index 5f7a293e36fdf5ecf55bb3e192509bfd7ad8da17..b4df8e521aba75786c61690db405655d686cfa7f 100644
--- a/src/lookup.h
+++ b/src/lookup.h
@@ -236,6 +236,7 @@ class V8_EXPORT_PRIVATE LookupIterator final BASE_EMBEDDED {
   Representation representation() const {
     return property_details().representation();
   }
+  PropertyConstness constness() const { return property_details().constness(); }
   FieldIndex GetFieldIndex() const;
   Handle<FieldType> GetFieldType() const;
   int GetFieldDescriptorIndex() const;
@@ -252,7 +253,7 @@ class V8_EXPORT_PRIVATE LookupIterator final BASE_EMBEDDED {
   }
   Handle<InterceptorInfo> GetInterceptorForFailedAccessCheck() const;
   Handle<Object> GetDataValue() const;
-  void WriteDataValue(Handle<Object> value);
+  void WriteDataValue(Handle<Object> value, bool initializing_store);
   inline void UpdateProtector() {
     if (IsElement()) return;
     if (*name_ == heap()->is_concat_spreadable_symbol() ||
@@ -303,6 +304,7 @@ class V8_EXPORT_PRIVATE LookupIterator final BASE_EMBEDDED {
   template <bool is_element>
   void RestartInternal(InterceptorState interceptor_state);
   Handle<Object> FetchValue() const;
+  bool IsConstFieldValueEqualTo(Object* value) const;
   template <bool is_element>
   void ReloadPropertyInformation();