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 e294e534a358de47784ac80e63cd33f3da038a7a..cbb8a78d0f5c0be0533e8c92a3e5c1e017d17513 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -3851,6 +3851,8 @@ 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(
@@ -9595,14 +9597,15 @@ 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