Consolidated property counting methods a bit.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 6edd6cce9a0b2e7ae0efb8365bead28a050c0e1e..17e66d704ccf86c2b2b3c663b661c40f093dfd84 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1807,9 +1807,7 @@ class JSObject: public JSReceiver {
 
   // Returns the number of properties on this object filtering out properties
   // with the specified attributes (ignoring interceptors).
-  int NumberOfLocalProperties(PropertyAttributes filter);
-  // Returns the number of enumerable properties (ignoring interceptors).
-  int NumberOfEnumProperties();
+  int NumberOfLocalProperties(PropertyAttributes filter = NONE);
   // Fill in details for properties into storage starting at the specified
   // index.
   void GetLocalPropertyNames(FixedArray* storage, int index);
@@ -4638,8 +4636,9 @@ class Map: public HeapObject {
   // Returns the next free property index (only valid for FAST MODE).
   int NextFreePropertyIndex();
 
-  // Returns the number of properties described in instance_descriptors.
-  int NumberOfDescribedProperties();
+  // Returns the number of properties described in instance_descriptors
+  // filtering out properties with the specified attributes.
+  int NumberOfDescribedProperties(PropertyAttributes filter = NONE);
 
   // Casting.
   static inline Map* cast(Object* obj);