Revert of Remove more dead code after Object.observe removal

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 406831d71b424d2407cc9d2abc92ca7e288450c3..b07f3a3ad49335e1dfa0a55000fcad59ad8dcf61 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1129,10 +1129,6 @@
   MUST_USE_RESULT static MaybeHandle<JSReceiver> ToObject(
       Isolate* isolate, Handle<Object> object, Handle<Context> context);
 
-  // ES6 section 9.2.1.2, OrdinaryCallBindThis for sloppy callee.
-  MUST_USE_RESULT static MaybeHandle<JSReceiver> ConvertReceiver(
-      Isolate* isolate, Handle<Object> object);
-
   // ES6 section 7.1.14 ToPropertyKey
   MUST_USE_RESULT static inline MaybeHandle<Name> ToName(Isolate* isolate,
                                                          Handle<Object> input);
@@ -1159,10 +1155,6 @@
   // ES6 section 7.1.12 ToString
   MUST_USE_RESULT static MaybeHandle<String> ToString(Isolate* isolate,
                                                       Handle<Object> input);
-
-  // ES6 section 7.1.14 ToPropertyKey
-  MUST_USE_RESULT static MaybeHandle<Object> ToPropertyKey(
-      Isolate* isolate, Handle<Object> value);
 
   // ES6 section 7.1.15 ToLength
   MUST_USE_RESULT static MaybeHandle<Object> ToLength(Isolate* isolate,
@@ -2186,6 +2178,13 @@
   MUST_USE_RESULT static Maybe<PropertyAttributes>
       GetPropertyAttributesWithFailedAccessCheck(LookupIterator* it);
 
+  // Retrieves an AccessorPair property from the given object. Might return
+  // undefined if the property doesn't exist or is of a different kind.
+  MUST_USE_RESULT static MaybeHandle<Object> GetAccessor(
+      Handle<JSObject> object,
+      Handle<Name> name,
+      AccessorComponent component);
+
   // Defines an AccessorPair property on the given object.
   // TODO(mstarzinger): Rename to SetAccessor().
   static MaybeHandle<Object> DefineAccessor(Handle<JSObject> object,
@@ -2298,6 +2297,15 @@
 
   void CollectOwnPropertyNames(KeyAccumulator* keys,
                                PropertyFilter filter = ALL_PROPERTIES);
+
+  // Returns the number of properties on this object filtering out properties
+  // with the specified attributes (ignoring interceptors).
+  // TODO(jkummerow): Deprecated, only used by Object.observe.
+  int NumberOfOwnElements(PropertyFilter filter);
+  // Returns the number of elements on this object filtering out elements
+  // with the specified attributes (ignoring interceptors).
+  // TODO(jkummerow): Deprecated, only used by Object.observe.
+  int GetOwnElementKeys(FixedArray* storage, PropertyFilter filter);
 
   static void CollectOwnElementKeys(Handle<JSObject> object,
                                     KeyAccumulator* keys,
@@ -3481,15 +3489,22 @@
 
   // Returns the number of elements in the dictionary filtering out properties
   // with the specified attributes.
+  // TODO(jkummerow): Deprecated, only used by Object.observe.
   int NumberOfElementsFilterAttributes(PropertyFilter filter);
 
   // Returns the number of enumerable elements in the dictionary.
+  // TODO(jkummerow): Deprecated, only used by Object.observe.
   int NumberOfEnumElements() {
     return NumberOfElementsFilterAttributes(ENUMERABLE_STRINGS);
   }
 
   enum SortMode { UNSORTED, SORTED };
 
+  // Fill in details for properties into storage.
+  // Returns the number of properties added.
+  // TODO(jkummerow): Deprecated, only used by Object.observe.
+  int CopyKeysTo(FixedArray* storage, int index, PropertyFilter filter,
+                 SortMode sort_mode);
   // Collect the keys into the given KeyAccumulator, in ascending chronological
   // order of property creation.
   static void CollectKeysTo(Handle<Dictionary<Derived, Shape, Key> > dictionary,