Reland of [stubs] KeyedStoreGeneric: inline dictionary property stores

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 13dee423200c8fa25dae6d6d5f719ee6b52df489..bde95cc6f725d0b3b9e19a30235049b4b5432dc8 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -3847,6 +3847,8 @@ class Dictionary: public HashTable<Derived, Shape, Key> {
   static const int kMaxNumberKeyIndex = DerivedHashTable::kPrefixStartIndex;
   static const int kNextEnumerationIndexIndex = kMaxNumberKeyIndex + 1;
 
+  static const bool kIsEnumerable = Shape::kIsEnumerable;
+
  protected:
   // Generic at put operation.
   MUST_USE_RESULT static Handle<Derived> AtPut(
@@ -9586,14 +9588,15 @@ class Symbol: public Name {
   static const int kFlagsOffset = kNameOffset + kPointerSize;
   static const int kSize = kFlagsOffset + kPointerSize;
 
+  // Flags layout.
+  static const int kPrivateBit = 0;
+  static const int kWellKnownSymbolBit = 1;
+
   typedef FixedBodyDescriptor<kNameOffset, kFlagsOffset, kSize> BodyDescriptor;
 
   void SymbolShortPrint(std::ostream& os);
 
  private:
-  static const int kPrivateBit = 0;
-  static const int kWellKnownSymbolBit = 1;
-
   const char* PrivateSymbolToName() const;
 
 #if TRACE_MAPS