style: comments changes about error handling

* data/skeletons/glr.c, data/skeletons/lalr1.cc, data/skeletons/lalr1.d,
* data/skeletons/lalr1.java, data/skeletons/yacc.c: here.
* data/skeletons/lalr1.cc: Reduce scope.

data/skeletons/glr.c

@@ -2353,7 +2353,7 @@ yyrecoverSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
     yycompressStack (yystackp);
   }
 
-  /* Now pop stack until we find a state that shifts the error token.  */
+  /* Pop stack until we find a state that shifts the error token.  */
   yystackp->yyerrState = 3;
   while (yystackp->yytops.yystates[0] != YY_NULLPTR)
     {

data/skeletons/lalr1.cc

@@ -1124,32 +1124,33 @@ b4_dollar_popdef])[]dnl
   `-------------------------------------------------------------*/
   yyerrlab1:
     yyerrstatus_ = 3;   // Each real token shifted decrements this.
+    // Pop stack until we find a state that shifts the error token.
+    for (;;)
+      {
+        yyn = yypact_[+yystack_[0].state];
+        if (!yy_pact_value_is_default_ (yyn))
+          {
+            yyn += symbol_kind::]b4_symbol_prefix[YYERROR;
+            if (0 <= yyn && yyn <= yylast_
+                && yycheck_[yyn] == symbol_kind::]b4_symbol_prefix[YYERROR)
+              {
+                yyn = yytable_[yyn];
+                if (0 < yyn)
+                  break;
+              }
+          }
+
+        // Pop the current state because it cannot handle the error token.
+        if (yystack_.size () == 1)
+          YYABORT;
+]b4_locations_if([[
+        yyerror_range[1].location = yystack_[0].location;]])[
+        yy_destroy_ ("Error: popping", yystack_[0]);
+        yypop_ ();
+        YY_STACK_PRINT ();
+      }
     {
       stack_symbol_type error_token;
-      for (;;)
-        {
-          yyn = yypact_[+yystack_[0].state];
-          if (!yy_pact_value_is_default_ (yyn))
-            {
-              yyn += symbol_kind::]b4_symbol_prefix[YYERROR;
-              if (0 <= yyn && yyn <= yylast_
-                  && yycheck_[yyn] == symbol_kind::]b4_symbol_prefix[YYERROR)
-                {
-                  yyn = yytable_[yyn];
-                  if (0 < yyn)
-                    break;
-                }
-            }
-
-          // Pop the current state because it cannot handle the error token.
-          if (yystack_.size () == 1)
-            YYABORT;
-]b4_locations_if([[
-          yyerror_range[1].location = yystack_[0].location;]])[
-          yy_destroy_ ("Error: popping", yystack_[0]);
-          yypop_ ();
-          YY_STACK_PRINT ();
-        }
 ]b4_locations_if([[
       yyerror_range[2].location = yyla.location;
       YYLLOC_DEFAULT (error_token.location, yyerror_range, 2);]])[

data/skeletons/lalr1.d

@@ -618,6 +618,7 @@ m4_popdef([b4_at_dollar])])dnl
       case YYERRLAB1:
         yyerrstatus_ = 3;       /* Each real token shifted decrements this.  */
 
+        // Pop stack until we find a state that shifts the error token.
         for (;;)
         {
           yyn = yypact_[yystate];

data/skeletons/lalr1.java

@@ -726,6 +726,7 @@ b4_dollar_popdef[]dnl
       case YYERRLAB1:
         yyerrstatus_ = 3;       /* Each real token shifted decrements this.  */
 
+        // Pop stack until we find a state that shifts the error token.
         for (;;)
           {
             yyn = yypact_[yystate];

data/skeletons/yacc.c

@@ -1998,6 +1998,7 @@ yyerrorlab:
 yyerrlab1:
   yyerrstatus = 3;      /* Each real token shifted decrements this.  */
 
+  // Pop stack until we find a state that shifts the error token.
   for (;;)
     {
       yyn = yypact[yystate];