Now it is used only for wheter `opt_paren_args` is `none`.  Introduce
a new special node to distinguish an empty parentheses from it .

89cfc152071 removed the definition of these functions.

Introduce another semantic value stack for Ripper so that
Ripper can manage both Node and Ruby Object separately.
This rearchitectutre of Ripper solves these issues.
Therefore adding test cases for them.

* [Bug 10436] https://bugs.ruby-lang.org/issues/10436
* [Bug 18988] https://bugs.ruby-lang.org/issues/18988
* [Bug 20055] https://bugs.ruby-lang.org/issues/20055

Checked the differences of `Ripper.sexp` for files under `/test/ruby`
are only on test_pattern_matching.rb.
The differences comes from the differences between
`new_hash_pattern_tail` functions between parser and Ripper.
Ripper `new_hash_pattern_tail` didn’t call `assignable` then
`kw_rest_arg` wasn’t marked as local variable.
This is also fixed by this commit.

```
--- a/./tmp/before/test_pattern_matching.rb
+++ b/./tmp/after/test_pattern_matching.rb
@@ -3607,7 +3607,7 @@
                  [:in,
                   [:hshptn, nil, [], [:var_field, [:@ident, “a”, [984, 13]]]],
                   [[:binary,
-                    [:vcall, [:@ident, “a”, [985, 10]]],
+                    [:var_ref, [:@ident, “a”, [985, 10]]],
                     :==,
                     [:hash, nil]]],
                   nil]]],
@@ -3662,7 +3662,7 @@
                  [:in,
                   [:hshptn, nil, [], [:var_field, [:@ident, “a”, [993, 13]]]],
                   [[:binary,
-                    [:vcall, [:@ident, “a”, [994, 10]]],
+                    [:var_ref, [:@ident, “a”, [994, 10]]],
                     :==,
                     [:hash,
                      [:assoclist_from_args,
@@ -3813,7 +3813,7 @@
                    [:command,
                     [:@ident, “raise”, [1022, 10]],
                     [:args_add_block,
-                     [[:vcall, [:@ident, “b”, [1022, 16]]]],
+                     [[:var_ref, [:@ident, “b”, [1022, 16]]]],
                      false]]],
                   [:else, [[:var_ref, [:@kw, “true”, [1024, 10]]]]]]]],
                nil,
@@ -3876,7 +3876,7 @@
                      [:@int, “0”, [1033, 15]]],
                     :“&&“,
                     [:binary,
-                     [:vcall, [:@ident, “b”, [1033, 20]]],
+                     [:var_ref, [:@ident, “b”, [1033, 20]]],
                      :==,
                      [:hash, nil]]]],
                   nil]]],
@@ -3946,7 +3946,7 @@
                      [:@int, “0”, [1042, 15]]],
                     :“&&“,
                     [:binary,
-                     [:vcall, [:@ident, “b”, [1042, 20]]],
+                     [:var_ref, [:@ident, “b”, [1042, 20]]],
                      :==,
                      [:hash,
                       [:assoclist_from_args,
@@ -5206,7 +5206,7 @@
                      [[:assoc_new,
                        [:@label, “c:“, [1352, 22]],
                        [:@int, “0”, [1352, 25]]]]]],
-                   [:vcall, [:@ident, “r”, [1352, 29]]]],
+                   [:var_ref, [:@ident, “r”, [1352, 29]]]],
                   false]]],
                [:binary,
                 [:call,
@@ -5299,7 +5299,7 @@
                       [:assoc_new,
                        [:@label, “c:“, [1367, 34]],
                        [:@int, “0”, [1367, 37]]]]]],
-                   [:vcall, [:@ident, “r”, [1367, 41]]]],
+                   [:var_ref, [:@ident, “r”, [1367, 41]]]],
                   false]]],
                [:binary,
                 [:call,
@@ -5931,7 +5931,7 @@
              [:in,
               [:hshptn, nil, [], [:var_field, [:@ident, “r”, [1533, 11]]]],
               [[:binary,
-                [:vcall, [:@ident, “r”, [1534, 8]]],
+                [:var_ref, [:@ident, “r”, [1534, 8]]],
                 :==,
                 [:hash,
                  [:assoclist_from_args,
```

Introduce Universal Parser mode for the parser.
This commit includes these changes:

* Introduce `UNIVERSAL_PARSER` macro. All of CRuby related functions
  are passed via `struct rb_parser_config_struct` when this macro is enabled.
* Add CI task with 'cppflags=-DUNIVERSAL_PARSER' for ubuntu.