Reorganize object type enum, such that proxies are no longer in the middle

src/macros.py

Index: src/macros.py
diff --git a/src/macros.py b/src/macros.py
index e3d1e03871125eb153db73a043b26aa69a54f2e6..473d5bac94d94e205a0408c39b25b44d5068ec4c 100644
--- a/src/macros.py
+++ b/src/macros.py
@@ -119,6 +119,7 @@ macro FLOOR(arg)                = $floor(arg);
 # This is the same as being either a function or an object in V8 terminology.
 # In addition, an undetectable object is also included by this.
 macro IS_SPEC_OBJECT(arg) = (%_IsSpecObject(arg));
+macro IS_SPEC_FUNCTION(arg) = (%_ClassOf(arg) == 'Function');
 
 # Inline macros. Use %IS_VAR to make sure arg is evaluated only once.
 macro NUMBER_IS_NAN(arg) = (!%_IsSmi(%IS_VAR(arg)) && !(arg == arg));