Improve lexer_expect_object_literal_id option handling (#2436)

This patch allows to add further options flags to `lexer_expect_object_literal_id` to handle unique behaviors more easily
also substitutes `PARSER_IS_CLASS` flag hence it is removed.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

jerry-core/parser/js/js-lexer.h

@@ -208,6 +208,17 @@ typedef enum
   LEXER_NO_SKIP_SPACES = (1u << 1)           /**< ignore skip spaces */
 } lexer_newline_flags_t;
 
+/**
+ * Lexer object identifier parse options.
+ */
+typedef enum
+{
+  LEXER_OBJ_IDENT_NO_OPTS = (1u << 0),          /**< no options */
+  LEXER_OBJ_IDENT_ONLY_IDENTIFIERS = (1u << 1), /**< only identifiers are accepted */
+  LEXER_OBJ_IDENT_CLASS_METHOD = (1u << 2),     /**< expect identifier inside a class body */
+} lexer_obj_ident_opts_t;
+
+
 /**
  * Lexer literal object types.
  */