MDEV-40740: Optimizer Context Replay: innodb.xa_unlock_unmodified fails assert

Optimizer Context code changed format_and_store_row() to check both
table->read_set and table->write_set (when required). It used to
use one of those depending on the lock level.

But we don't set the table->read_set bit so we can get an assertion
failure when dumping the column value.

This is fairly rare as Optimizer Context now reads all columns, and the
only other user is statements like "DBUG_PRINT("dml", dbug_format_row(..."

Author: spetrunia

sql/filesort.cc

@@ -3104,11 +3104,19 @@ void format_and_store_row(TABLE *table, const uchar *rec, bool print_names,
     bool require_quote= false;
 
     bool print_col= false;
-    if ((check_also_write_set &&
-         bitmap_is_set(table->write_set, field->field_index)) ||
-        (table->read_set &&
-         bitmap_is_set(table->read_set, field->field_index)))
+    bool clear_read_bit= false;
+    if (table->read_set && bitmap_is_set(table->read_set, field->field_index))
       print_col= true;
+    else
+    {
+      if ((check_also_write_set && bitmap_is_set(table->write_set,
+                                                 field->field_index)))
+      {
+        print_col= true;
+        bitmap_set_bit(table->read_set, field->field_index);
+        clear_read_bit= true;
+      }
+    }
     if (!print_col)
       continue;
 
@@ -3149,6 +3157,8 @@ void format_and_store_row(TABLE *table, const uchar *rec, bool print_names,
         }
         field->val_str(&tmp);
       }
+      if (clear_read_bit)
+        bitmap_clear_bit(table->read_set, field->field_index);
       /*
         Emit non-empty values as a hex literal whenever converting field's
         charset to the output charset conversion is lossy; otherwise emit the