MDEV-7975: sporadic failure in test case rpl.rpl_gtid_startpos

Add some suppressions that were missing. They are for if a STOP SLAVE is
executed early during IO thread startup, when it is negotiating with the
master. The master connection may be killed in the middle of a
mysql_real_query(), which is not a test failure if it is a network error.

This also caught one real code error, fixed with this commit: The I/O thread
would fail to automatically reconnect if a network error happened while
fetching the value of @@GLOBAL.gtid_domain_id.

mysql-test/include/mtr_warnings.sql

@@ -227,6 +227,12 @@ INSERT INTO global_suppressions VALUES
  ("Slave I/O: Notifying master by SET @master_binlog_checksum= @@global.binlog_checksum failed with error.*"),
  ("Slave I/O: Setting master-side filtering of @@skip_replication failed with error:.*"),
  ("Slave I/O: Setting @mariadb_slave_capability failed with error:.*"),
+ ("Slave I/O: Get master @@GLOBAL.gtid_domain_id failed with error.*"),
+ ("Slave I/O: Setting @slave_connect_state failed with error.*"),
+ ("Slave I/O: Setting @slave_gtid_strict_mode failed with error.*"),
+ ("Slave I/O: Setting @slave_gtid_ignore_duplicates failed with error.*"),
+ ("Slave I/O: Setting @slave_until_gtid failed with error.*"),
+ ("Slave I/O: Get master GTID position failed with error.*"),
  ("THE_LAST_SUPPRESSION")||
 
 

mysql-test/mysql-test-run.pl

@@ -4839,6 +4839,12 @@ sub extract_warning_lines ($$) {
      qr/Slave I\/O: Get master clock failed with error:.*/,
      qr/Slave I\/O: Get master COLLATION_SERVER failed with error:.*/,
      qr/Slave I\/O: Get master TIME_ZONE failed with error:.*/,
+     qr/Slave I\/O: Get master \@\@GLOBAL.gtid_domain_id failed with error:.*/,
+     qr/Slave I\/O: Setting \@slave_connect_state failed with error:.*/,
+     qr/Slave I\/O: Setting \@slave_gtid_strict_mode failed with error:.*/,
+     qr/Slave I\/O: Setting \@slave_gtid_ignore_duplicates failed with error:.*/,
+     qr/Slave I\/O: Setting \@slave_until_gtid failed with error:.*/,
+     qr/Slave I\/O: Get master GTID position failed with error:.*/,
      qr/Slave I\/O: error reconnecting to master '.*' - retry-time: [1-3]  retries/,
      qr/Slave I\/0: Master command COM_BINLOG_DUMP failed/,
      qr/Error reading packet/,

sql/slave.cc

@@ -2004,11 +2004,21 @@ after_set_capability:
         !(master_row= mysql_fetch_row(master_res)))
     {
       err_code= mysql_errno(mysql);
-      errmsg= "The slave I/O thread stops because master does not support "
-        "MariaDB global transaction id. A fatal error is encountered when "
-        "it tries to SELECT @@GLOBAL.gtid_domain_id.";
-      sprintf(err_buff, "%s Error: %s", errmsg, mysql_error(mysql));
-      goto err;
+      if (is_network_error(err_code))
+      {
+        mi->report(ERROR_LEVEL, err_code, NULL,
+                   "Get master @@GLOBAL.gtid_domain_id failed with error: %s",
+                   mysql_error(mysql));
+        goto network_err;
+      }
+      else
+      {
+        errmsg= "The slave I/O thread stops because master does not support "
+          "MariaDB global transaction id. A fatal error is encountered when "
+          "it tries to SELECT @@GLOBAL.gtid_domain_id.";
+        sprintf(err_buff, "%s Error: %s", errmsg, mysql_error(mysql));
+        goto err;
+      }
     }
     mysql_free_result(master_res);
     master_res= NULL;