Handle parenthesized expressions.

src/libs/glsl/glsl.g

@@ -493,21 +493,21 @@ case $rule_number: {
 primary_expression ::= variable_identifier ;
 /.
 case $rule_number: {
-    // ast(1) = new ...AST(...);
+    // nothing to do.
 }   break;
 ./
 
 primary_expression ::= LEFT_PAREN expression RIGHT_PAREN ;
 /.
 case $rule_number: {
-    // ast(1) = new ...AST(...);
+    ast(1) = ast(2);
 }   break;
 ./
 
 postfix_expression ::= primary_expression ;
 /.
 case $rule_number: {
-    // ast(1) = new ...AST(...);
+    // nothing to do.
 }   break;
 ./
 

src/libs/glsl/glslparser.cpp

@@ -192,19 +192,19 @@ case 3: {
 #line 494 "./glsl.g"
 
 case 4: {
-    // ast(1) = new ...AST(...);
+    // nothing to do.
 }   break;
 
 #line 501 "./glsl.g"
 
 case 5: {
-    // ast(1) = new ...AST(...);
+    ast(1) = ast(2);
 }   break;
 
 #line 508 "./glsl.g"
 
 case 6: {
-    // ast(1) = new ...AST(...);
+    // nothing to do.
 }   break;
 
 #line 515 "./glsl.g"