Revert of Parse arrow functions at proper precedence level

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index 6e9390f6e3f62ebfe9d168b25993ffb0fef3a47c..1366041387215bc4c018c4b1650d39ff5f6549c4 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -88,8 +88,7 @@
   V(ThisFunction)               \
   V(SuperPropertyReference)     \
   V(SuperCallReference)         \
-  V(CaseClause)                 \
-  V(EmptyParentheses)
+  V(CaseClause)
 
 #define AST_NODE_LIST(V)                        \
   DECLARATION_NODE_LIST(V)                      \
@@ -2846,17 +2845,6 @@
   VariableProxy* this_var_;
   VariableProxy* new_target_var_;
   VariableProxy* this_function_var_;
-};
-
-
-// This class is produced when parsing the () in arrow functions without any
-// arguments and is not actually a valid expression.
-class EmptyParentheses final : public Expression {
- public:
-  DECLARE_NODE_TYPE(EmptyParentheses)
-
- private:
-  EmptyParentheses(Zone* zone, int pos) : Expression(zone, pos) {}
 };
 
 
@@ -3645,10 +3633,6 @@
                                           this_function_var, pos);
   }
 
-  EmptyParentheses* NewEmptyParentheses(int pos) {
-    return new (zone_) EmptyParentheses(zone_, pos);
-  }
-
  private:
   Zone* zone_;
   AstValueFactory* ast_value_factory_;