Plumbing changes to merge various element kind implementaions.

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index 7ed3579edd74f2660b1be4b89c0bf40ad1bc636c..bfcb346d66b3bacc69b5a7a0ab95dde9e6695fed 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -261,17 +261,9 @@ class Expression: public AstNode {
     return Handle<Map>();
   }
 
-  ExternalArrayType external_array_type() const {
-    return external_array_type_;
-  }
-  void set_external_array_type(ExternalArrayType array_type) {
-    external_array_type_ = array_type;
-  }
-
   unsigned id() const { return id_; }
 
  private:
-  ExternalArrayType external_array_type_;
   unsigned id_;
 };