Bug #11766306: 59393: have_innodb=yes when mysqld started with --skip-innodb

Initialized correctly the have_innodb variable so that when the plugin is not initialized it
stays "disabled" instead of "yes".
Test suite added.

mysql-test/r/bootstrap.result

@@ -6,3 +6,15 @@ set @my_max_allowed_packet= @@max_allowed_packet;
 set global max_allowed_packet=100*@@max_allowed_packet;
 set global max_allowed_packet=@my_max_allowed_packet;
 drop table t1;
+End of 5.1 tests
+#
+# Bug #11766306: 59393: HAVE_INNODB=YES WHEN MYSQLD 
+#  STARTED WITH --SKIP-INNODB
+#
+SHOW VARIABLES LIKE 'have_innodb';
+Variable_name	Value
+have_innodb	DISABLED
+SELECT SUPPORT FROM INFORMATION_SCHEMA.ENGINES WHERE engine='innodb';
+SUPPORT
+NO
+End of 5.5 tests

mysql-test/t/bootstrap.test

@@ -49,3 +49,15 @@ remove_file $MYSQLTEST_VARDIR/tmp/long_query.sql;
 set global max_allowed_packet=@my_max_allowed_packet;
 drop table t1;
 
+--echo End of 5.1 tests
+
+--echo #
+--echo # Bug #11766306: 59393: HAVE_INNODB=YES WHEN MYSQLD 
+--echo #  STARTED WITH --SKIP-INNODB
+--echo #
+
+# need the --skip-innodb option present for the test to succeed
+SHOW VARIABLES LIKE 'have_innodb';
+SELECT SUPPORT FROM INFORMATION_SCHEMA.ENGINES WHERE engine='innodb';
+
+--echo End of 5.5 tests

sql/sys_vars.cc

@@ -2766,7 +2766,7 @@ static Sys_var_charptr Sys_slow_log_path(
        ON_CHECK(check_log_path), ON_UPDATE(fix_slow_log_file));
 
 /// @todo deprecate these four legacy have_PLUGIN variables and use I_S instead
-export SHOW_COMP_OPTION have_csv, have_innodb;
+export SHOW_COMP_OPTION have_csv, have_innodb= SHOW_OPTION_DISABLED;
 export SHOW_COMP_OPTION have_ndbcluster, have_partitioning;
 static Sys_var_have Sys_have_csv(
        "have_csv", "have_csv",